General method to find sum of binomial
Specifically I want to ask the method to solve
$$sum_{k=0}^n binom{4n+b}{4k}; b=[0,1,2,3]$$
And how to solve series of type
$$sum_{k=0}^n binom{an+b}{ak}; a=[1,2,3,...], b=[0,1,2,...,a-1]$$
combinatorics complex-numbers binomial-coefficients
add a comment |
Specifically I want to ask the method to solve
$$sum_{k=0}^n binom{4n+b}{4k}; b=[0,1,2,3]$$
And how to solve series of type
$$sum_{k=0}^n binom{an+b}{ak}; a=[1,2,3,...], b=[0,1,2,...,a-1]$$
combinatorics complex-numbers binomial-coefficients
series multisection
– Lord Shark the Unknown
Nov 22 '18 at 7:38
For $4k$, see Arthur T. Benjamin, Jacob N. Scott, Third and fourth binomial coefficients. For $ak$, there is a formula resulting in an $a$-term sum, involving roots of unity; but that's not very explicit in my opinion.
– darij grinberg
Nov 22 '18 at 7:38
add a comment |
Specifically I want to ask the method to solve
$$sum_{k=0}^n binom{4n+b}{4k}; b=[0,1,2,3]$$
And how to solve series of type
$$sum_{k=0}^n binom{an+b}{ak}; a=[1,2,3,...], b=[0,1,2,...,a-1]$$
combinatorics complex-numbers binomial-coefficients
Specifically I want to ask the method to solve
$$sum_{k=0}^n binom{4n+b}{4k}; b=[0,1,2,3]$$
And how to solve series of type
$$sum_{k=0}^n binom{an+b}{ak}; a=[1,2,3,...], b=[0,1,2,...,a-1]$$
combinatorics complex-numbers binomial-coefficients
combinatorics complex-numbers binomial-coefficients
edited Nov 22 '18 at 7:38
Saurav Singh
asked Nov 22 '18 at 7:27


Saurav SinghSaurav Singh
183
183
series multisection
– Lord Shark the Unknown
Nov 22 '18 at 7:38
For $4k$, see Arthur T. Benjamin, Jacob N. Scott, Third and fourth binomial coefficients. For $ak$, there is a formula resulting in an $a$-term sum, involving roots of unity; but that's not very explicit in my opinion.
– darij grinberg
Nov 22 '18 at 7:38
add a comment |
series multisection
– Lord Shark the Unknown
Nov 22 '18 at 7:38
For $4k$, see Arthur T. Benjamin, Jacob N. Scott, Third and fourth binomial coefficients. For $ak$, there is a formula resulting in an $a$-term sum, involving roots of unity; but that's not very explicit in my opinion.
– darij grinberg
Nov 22 '18 at 7:38
series multisection
– Lord Shark the Unknown
Nov 22 '18 at 7:38
series multisection
– Lord Shark the Unknown
Nov 22 '18 at 7:38
For $4k$, see Arthur T. Benjamin, Jacob N. Scott, Third and fourth binomial coefficients. For $ak$, there is a formula resulting in an $a$-term sum, involving roots of unity; but that's not very explicit in my opinion.
– darij grinberg
Nov 22 '18 at 7:38
For $4k$, see Arthur T. Benjamin, Jacob N. Scott, Third and fourth binomial coefficients. For $ak$, there is a formula resulting in an $a$-term sum, involving roots of unity; but that's not very explicit in my opinion.
– darij grinberg
Nov 22 '18 at 7:38
add a comment |
1 Answer
1
active
oldest
votes
I am sure that you will enjoy the result !
If $$S_n=sum_{k=0}^n binom{4n+b}{4k}$$ then a CAS gives
$$4S_n=2^{frac{4 n+b}{2} } left((-1)^b, 2^{frac{4 n+b}{2} } cos (pi b)+cos
left(frac{ (4 n+b)pi}{4} right)+(-1)^b cos left(frac{3(4
n+b)pi}{4} right)right)-$$ $$4 binom{4 n+b}{4 n+4} ,
_5F_4left(1,frac{4-b}{4},frac{5-b}{4},frac{6-b}{4},frac
{7-b}{4};frac{4n+5}{4},frac{4n+6}{4},frac{4n+7}{4},frac{4n+8}{4};1right)$$ where appears the generalized hypergeometric function.
For the first values of $b$, the sequences can be found in $OEIS$.
$$left(
begin{array}{cc}
b & text{OEIS sequence} \
0 & text{A070775} \
1 & text{A090407} \
2 & text{A001025} \
3 & text{A090408}
end{array}
right)$$
Be sure that I did not make this by myself.
add a comment |
Your Answer
StackExchange.ifUsing("editor", function () {
return StackExchange.using("mathjaxEditing", function () {
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
});
});
}, "mathjax-editing");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "69"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3008839%2fgeneral-method-to-find-sum-of-binomial%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
I am sure that you will enjoy the result !
If $$S_n=sum_{k=0}^n binom{4n+b}{4k}$$ then a CAS gives
$$4S_n=2^{frac{4 n+b}{2} } left((-1)^b, 2^{frac{4 n+b}{2} } cos (pi b)+cos
left(frac{ (4 n+b)pi}{4} right)+(-1)^b cos left(frac{3(4
n+b)pi}{4} right)right)-$$ $$4 binom{4 n+b}{4 n+4} ,
_5F_4left(1,frac{4-b}{4},frac{5-b}{4},frac{6-b}{4},frac
{7-b}{4};frac{4n+5}{4},frac{4n+6}{4},frac{4n+7}{4},frac{4n+8}{4};1right)$$ where appears the generalized hypergeometric function.
For the first values of $b$, the sequences can be found in $OEIS$.
$$left(
begin{array}{cc}
b & text{OEIS sequence} \
0 & text{A070775} \
1 & text{A090407} \
2 & text{A001025} \
3 & text{A090408}
end{array}
right)$$
Be sure that I did not make this by myself.
add a comment |
I am sure that you will enjoy the result !
If $$S_n=sum_{k=0}^n binom{4n+b}{4k}$$ then a CAS gives
$$4S_n=2^{frac{4 n+b}{2} } left((-1)^b, 2^{frac{4 n+b}{2} } cos (pi b)+cos
left(frac{ (4 n+b)pi}{4} right)+(-1)^b cos left(frac{3(4
n+b)pi}{4} right)right)-$$ $$4 binom{4 n+b}{4 n+4} ,
_5F_4left(1,frac{4-b}{4},frac{5-b}{4},frac{6-b}{4},frac
{7-b}{4};frac{4n+5}{4},frac{4n+6}{4},frac{4n+7}{4},frac{4n+8}{4};1right)$$ where appears the generalized hypergeometric function.
For the first values of $b$, the sequences can be found in $OEIS$.
$$left(
begin{array}{cc}
b & text{OEIS sequence} \
0 & text{A070775} \
1 & text{A090407} \
2 & text{A001025} \
3 & text{A090408}
end{array}
right)$$
Be sure that I did not make this by myself.
add a comment |
I am sure that you will enjoy the result !
If $$S_n=sum_{k=0}^n binom{4n+b}{4k}$$ then a CAS gives
$$4S_n=2^{frac{4 n+b}{2} } left((-1)^b, 2^{frac{4 n+b}{2} } cos (pi b)+cos
left(frac{ (4 n+b)pi}{4} right)+(-1)^b cos left(frac{3(4
n+b)pi}{4} right)right)-$$ $$4 binom{4 n+b}{4 n+4} ,
_5F_4left(1,frac{4-b}{4},frac{5-b}{4},frac{6-b}{4},frac
{7-b}{4};frac{4n+5}{4},frac{4n+6}{4},frac{4n+7}{4},frac{4n+8}{4};1right)$$ where appears the generalized hypergeometric function.
For the first values of $b$, the sequences can be found in $OEIS$.
$$left(
begin{array}{cc}
b & text{OEIS sequence} \
0 & text{A070775} \
1 & text{A090407} \
2 & text{A001025} \
3 & text{A090408}
end{array}
right)$$
Be sure that I did not make this by myself.
I am sure that you will enjoy the result !
If $$S_n=sum_{k=0}^n binom{4n+b}{4k}$$ then a CAS gives
$$4S_n=2^{frac{4 n+b}{2} } left((-1)^b, 2^{frac{4 n+b}{2} } cos (pi b)+cos
left(frac{ (4 n+b)pi}{4} right)+(-1)^b cos left(frac{3(4
n+b)pi}{4} right)right)-$$ $$4 binom{4 n+b}{4 n+4} ,
_5F_4left(1,frac{4-b}{4},frac{5-b}{4},frac{6-b}{4},frac
{7-b}{4};frac{4n+5}{4},frac{4n+6}{4},frac{4n+7}{4},frac{4n+8}{4};1right)$$ where appears the generalized hypergeometric function.
For the first values of $b$, the sequences can be found in $OEIS$.
$$left(
begin{array}{cc}
b & text{OEIS sequence} \
0 & text{A070775} \
1 & text{A090407} \
2 & text{A001025} \
3 & text{A090408}
end{array}
right)$$
Be sure that I did not make this by myself.
edited Nov 22 '18 at 12:08
answered Nov 22 '18 at 10:40
Claude LeiboviciClaude Leibovici
119k1157132
119k1157132
add a comment |
add a comment |
Thanks for contributing an answer to Mathematics Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
Use MathJax to format equations. MathJax reference.
To learn more, see our tips on writing great answers.
Some of your past answers have not been well-received, and you're in danger of being blocked from answering.
Please pay close attention to the following guidance:
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3008839%2fgeneral-method-to-find-sum-of-binomial%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
series multisection
– Lord Shark the Unknown
Nov 22 '18 at 7:38
For $4k$, see Arthur T. Benjamin, Jacob N. Scott, Third and fourth binomial coefficients. For $ak$, there is a formula resulting in an $a$-term sum, involving roots of unity; but that's not very explicit in my opinion.
– darij grinberg
Nov 22 '18 at 7:38