cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-10 of 33 results. Next

A052847 G.f.: 1 / Product_{k>=1} (1-x^k)^(k-1).

Original entry on oeis.org

1, 0, 1, 2, 4, 6, 12, 18, 33, 52, 88, 138, 229, 354, 568, 880, 1378, 2110, 3260, 4942, 7527, 11320, 17031, 25394, 37842, 55956, 82630, 121300, 177677, 258980, 376626, 545352, 787784, 1133764, 1627657, 2329020, 3324559, 4731396, 6717774, 9512060
Offset: 0

Views

Author

encyclopedia(AT)pommard.inria.fr, Jan 25 2000

Keywords

Comments

Euler transform of sequence [0,1,2,3,...]. - Michael Somos, Jul 02 2004
Number of partitions of n objects of 2 colors, where each part must contain at least one of each color. - Franklin T. Adams-Watters, Jan 23 2006
Number of partitions of n without 1s, one kind of 2s, two kinds of 3s, etc. - Joerg Arndt, Jul 31 2011
From Vaclav Kotesovec, Oct 17 2015: (Start)
In general, if v>=0 and g.f. = Product_{k>=1} 1/(1-x^(k+v))^k, then a(n) ~ d1(v) * n^(v^2/6 - 25/36) * exp(-Pi^4 * v^2 / (432*Zeta(3)) + 3*Zeta(3)^(1/3) * n^(2/3)/2^(2/3) - v * Pi^2 * n^(1/3) / (3 * 2^(4/3) * Zeta(3)^(1/3))) / (sqrt(3*Pi) * 2^(v^2/6 + 11/36) * Zeta(3)^(v^2/6 - 7/36)), where Zeta(3) = A002117.
d1(v) = exp(Integral_{x=0..infinity} (1/(x*exp((v-1)*x) * (exp(x)-1)^2) - (6*v^2-1) / (12*x*exp(x)) + v/x^2 - 1/x^3) dx).
d1(v) = (exp(Zeta'(-1) - v*Zeta'(0))) / Product_{j=0..v-1} j!, where Zeta'(0) = -A075700, Zeta'(-1) = A084448 and Product_{j=0..v-1} j! = A000178(v-1).
d1(v) = exp(1/12) * (2*Pi)^(v/2) / (A * G(v+1)), where A = A074962 is the Glaisher-Kinkelin constant and G is the Barnes G-function.
(End)

Examples

			1 + x^2 + 2*x^3 + 4*x^4 + 6*x^5 + 12*x^6 + 18*x^7 + 33*x^8 + 52*x^9 + ...
From _Gus Wiseman_, Jan 22 2019: (Start)
The partitions described in Franklin T. Adams-Watters's comment are (n = 2 through 6):
  {{12}}  {{112}}  {{1112}}    {{11112}}    {{111112}}
          {{122}}  {{1122}}    {{11122}}    {{111122}}
                   {{1222}}    {{11222}}    {{111222}}
                   {{12}{12}}  {{12222}}    {{112222}}
                               {{12}{112}}  {{122222}}
                               {{12}{122}}  {{112}{112}}
                                            {{112}{122}}
                                            {{12}{1112}}
                                            {{12}{1122}}
                                            {{12}{1222}}
                                            {{122}{122}}
                                            {{12}{12}{12}}
(End)
		

Crossrefs

Cf. A000219 (v=0), A052847 (v=1), A263358 (v=2), A263359 (v=3), A263360 (v=4), A263361 (v=5), A263362 (v=6), A263363 (v=7), A263364 (v=8).

Programs

  • Maple
    spec := [S,{B=Sequence(Z,1 <= card),C=Prod(B,B),S= Set(C)},unlabeled]: seq(combstruct[count](spec, size=n), n=0..20);
    with(numtheory): etr:= proc(p) local b; b:=proc(n) option remember; local d, j; if n=0 then 1 else add(add(d*p(d), d=divisors(j)) *b(n-j), j=1..n)/n fi end end: a:=etr(n-> n-1): seq(a(n), n=0..50); # Vaclav Kotesovec, Mar 04 2015 after Alois P. Heinz
  • Mathematica
    Clear[a]; a[n_]:= a[n] = 1/n*Sum[(DivisorSigma[2,k]-DivisorSigma[1,k])*a[n-k],{k,1,n}]; a[0]=1; Table[a[n],{n,0,100}] (* Vaclav Kotesovec, Mar 04 2015 *)
    nmax = 40; CoefficientList[Series[Product[1/(1-x^(k+1))^k, {k, 1, nmax}], {x, 0, nmax}], x] (* Vaclav Kotesovec, Oct 16 2015 *)
  • PARI
    {a(n) = if( n<0, 0, polcoeff( 1 / prod(k=1, n, (1 - x^k + x*O(x^n))^(k-1)), n))}

Formula

a(n) = 1/n*Sum_{k=1..n} (sigma[2](k)-sigma[1](k))*a(n-k).
G.f.: exp( Sum_{k>0} ( x^k / (1 - x^k) )^2 / k ).
G.f.: exp( sum(n>=0, (sigma[2](n)-sigma[1](n)) *x^n/n ) ). - Joerg Arndt, Jul 31 2011
a(n) ~ 2^(1/36) * Zeta(3)^(1/36) * exp(1/12 - Pi^4/(432*Zeta(3)) - Pi^2 * n^(1/3) / (3 * 2^(4/3) * Zeta(3)^(1/3)) + 3 * Zeta(3)^(1/3) * n^(2/3) / 2^(2/3)) / (A * 3^(1/2) * n^(19/36)), where A = A074962 = 1.2824271291... is the Glaisher-Kinkelin constant. - Vaclav Kotesovec, Mar 07 2015

Extensions

Edited by Vladeta Jovovic, Sep 10 2002

A240966 Decimal expansion of zeta'(-2) (the derivative of Riemann's zeta function at -2).

Original entry on oeis.org

0, 3, 0, 4, 4, 8, 4, 5, 7, 0, 5, 8, 3, 9, 3, 2, 7, 0, 7, 8, 0, 2, 5, 1, 5, 3, 0, 4, 7, 1, 1, 5, 4, 7, 7, 6, 6, 4, 7, 0, 0, 0, 4, 8, 3, 5, 4, 4, 9, 7, 3, 9, 3, 6, 2, 5, 2, 9, 7, 1, 8, 8, 9, 8, 5, 9, 0, 3, 7, 8, 1, 7, 9, 4, 4, 9, 3, 6, 8, 9, 8, 6, 7, 7, 7, 9, 4, 5, 8, 4, 8, 8, 0, 8, 7, 4, 4, 9, 5, 9, 7, 0, 3, 6
Offset: 0

Views

Author

Jean-François Alcover, Aug 05 2014

Keywords

Examples

			-0.030448457058393270780251530471154776647000483544973936252971889859...
		

Crossrefs

Cf. A084448 (zeta'(-1)), A075700 (zeta'(0)), A073002 (zeta'(2)), A244115 (zeta'(3)).

Programs

  • Mathematica
    Join[{0}, RealDigits[-Zeta[3]/(4*Pi^2), 10, 103] // First]

Formula

zeta'(-2) = -zeta(3)/(4*Pi^2).
Equals -log(A243262). - Vaclav Kotesovec, Feb 22 2015

A266262 Decimal expansion of zeta'(-11) (the derivative of Riemann's zeta function at -11) (negated).

Original entry on oeis.org

0, 1, 2, 7, 5, 2, 9, 8, 4, 4, 7, 9, 9, 6, 6, 6, 5, 6, 1, 1, 3, 5, 2, 2, 5, 2, 5, 4, 8, 8, 7, 2, 5, 7, 9, 8, 1, 5, 6, 2, 3, 8, 9, 3, 7, 0, 4, 9, 8, 7, 4, 2, 9, 2, 7, 9, 3, 2, 4, 6, 3, 6, 6, 6, 6, 1, 1, 4, 0, 7, 0, 2, 3, 2, 0, 6, 2, 1, 2, 4, 7, 4, 0, 9, 0, 4, 8, 1, 9, 3, 5, 4, 2
Offset: 0

Views

Author

G. C. Greubel, Dec 25 2015

Keywords

Examples

			-0.012752984479966656113522525488725798156238937049874292793246366661...
		

Crossrefs

Cf. A075700 (zeta'(0)), A084448 (zeta'(-1)), A240966 (zeta'(-2)), A259068 (zeta'(-3)), A259070 (zeta'(-5)), A259071 (zeta'(-6)), A259072 (zeta'(-7)), A259073 (zeta'(-8)), A266260 (zeta'(-9)), A266261 (zeta'(-10)), A266263 (zeta'(-12)), A260660 (zeta'(-13)), A266264 (zeta'(-14)), A266270 (zeta'(-15)), A266271 (zeta'(-16)), A266272 (zeta'(-17)), A266273 (zeta'(-18)), A266274 (zeta'(-19)), A266275 (zeta'(-20)).

Programs

  • Mathematica
    Join[{0}, RealDigits[Zeta'[-11], 10, 100] // First]

Formula

zeta'(-n) = HarmonicNumber(n)*BernoulliB(n+1)/(n+1) - log(A(n)), where A(n) is the n-th Bendersky constant.
zeta'(-11) = - 57844301/908107200 - log(A(11)).

Extensions

Keyword cons added by Rick L. Shepherd, May 29 2016

A260660 Decimal expansion of zeta'(-13) (the derivative of Riemann's zeta function at -13).

Original entry on oeis.org

0, 6, 3, 7, 4, 9, 8, 7, 3, 7, 4, 4, 5, 7, 6, 8, 8, 0, 2, 8, 6, 0, 3, 8, 6, 8, 1, 4, 7, 3, 3, 3, 5, 0, 5, 5, 6, 4, 8, 8, 2, 7, 3, 5, 5, 3, 1, 2, 7, 5, 8, 4, 9, 1, 3, 8, 5, 1, 0, 0, 8, 8, 5, 8, 8, 7, 7, 3, 7, 0, 6, 4, 2, 0, 1, 5, 6, 6, 6, 8, 7, 0, 9, 4, 7, 0, 9, 2, 6, 7, 8, 1, 5, 3, 5, 8, 2, 6, 3, 1, 8, 7, 8, 2, 4, 3, 7
Offset: 0

Views

Author

G. C. Greubel, Nov 13 2015

Keywords

Examples

			0.06374987374457688028603868147333505564882735...
		

Crossrefs

Cf. A075700 (zeta'(0)), A084448 (zeta'(-1)), A240966 (zeta'(-2)), A259068 (zeta'(-3)), A259069 (zeta'(-4)), A259070 (zeta'(-5)), A259071 (zeta'(-6)), A259072 (zeta'(-7)), A259073 (zeta'(-8)), A266260 (zeta'(-9)), A266261 (zeta'(-10)), A266262 (zeta'(-11)), A266263 (zeta'(-12)), A266264 (zeta'(-14)), A266270 (zeta'(-15)), A266271 (zeta'(-16)), A266272 (zeta'(-17)), A266273 (zeta'(-18)), A266274 (zeta'(-19)), A266275 (zeta'(-20)).

Programs

  • Mathematica
    N[Zeta'[-13]]
    Join[{0}, RealDigits[Zeta'[-13], 10, 1500] // First]
  • PARI
    zeta'(-13) \\ Altug Alkan, Nov 13 2015

Formula

zeta'(-n) = (BernoulliB(n+1)*HarmonicNumber(n))/(n+1) - log(A(n)), where A(n) is the n-th Bendersky constant, that is the n-th generalized Glaisher constant.
zeta'(-13) = (1145993/4324320) - log(A(13)).
zeta'(-13) = 1145993/4324320 - gamma/12 - log(2*Pi)/12 + 6081075*Zeta'(14) / (8*Pi^14), where gamma is the Euler-Mascheroni constant A001620. - Vaclav Kotesovec, Dec 05 2015

A266260 Decimal expansion of zeta'(-9) (the derivative of Riemann's zeta function at -9).

Original entry on oeis.org

0, 0, 3, 1, 3, 0, 1, 4, 5, 3, 1, 9, 7, 8, 8, 5, 7, 2, 7, 5, 4, 9, 2, 5, 7, 6, 8, 2, 9, 0, 7, 8, 5, 4, 4, 6, 7, 0, 2, 6, 6, 9, 3, 6, 5, 8, 6, 5, 4, 8, 1, 5, 1, 5, 9, 6, 4, 9, 0, 5, 1, 3, 3, 2, 0, 5, 4, 3, 4, 7, 1, 6, 3, 0, 1, 4, 2, 9, 6, 4, 3, 4, 9, 4, 3, 0, 9, 5, 1
Offset: 0

Views

Author

G. C. Greubel, Dec 25 2015

Keywords

Examples

			0.0031301453197885727549257682907854467026693658654815.....
		

Crossrefs

Cf. A075700 (zeta'(0)), A084448 (zeta'(-1)), A240966 (zeta'(-2)), A259068 (zeta'(-3)), A259069 (zeta'(-4)), A259070 (zeta'(-5)), A259071 (zeta'(-6)), A259072 (zeta'(-7)), A259073 (zeta'(-8)), A266261 (zeta'(-10)), A266262 (zeta'(-11)), A266263 (zeta'(-12)), A260660 (zeta'(-13)), A266264 (zeta'(-14)), A266270 (zeta'(-15)), A266271 (zeta'(-16)), A266272 (zeta'(-17)), A266273 (zeta'(-18)), A266274 (zeta'(-19)), A266275 (zeta'(-20)).

Programs

  • Mathematica
    Join[{0, 0}, RealDigits[Zeta'[-9], 10, 100] // First]
    N[Zeta'[-9], 100]

Formula

zeta'(-n) = HarmonicNumber(n)*BernoulliB(n+1)/(n+1) - log(A(n)), where A(n) is the n-th Bendersky constant.
zeta'(-9) = 7129/332640 - log(A(9)).

A266270 Decimal expansion of zeta'(-15) (the derivative of Riemann's zeta function at -15).

Original entry on oeis.org

4, 0, 0, 3, 1, 9, 3, 0, 2, 8, 0, 7, 7, 2, 5, 5, 9, 3, 8, 4, 3, 5, 8, 0, 3, 1, 7, 5, 2, 0, 3, 2, 0, 3, 6, 7, 2, 0, 1, 2, 6, 1, 2, 8, 6, 2, 6, 6, 2, 3, 2, 9, 4, 4, 2, 8, 4, 1, 0, 6, 9, 4, 2, 6, 3, 9, 0, 3, 0, 3, 3, 6, 0, 2, 9, 3, 1, 7, 2, 0, 0, 7, 6, 4, 2, 6, 1, 4, 6, 4, 2, 2, 2, 6, 4, 3, 9, 5, 4, 8, 4, 5, 7, 8, 4, 3, 1, 4, 3, 1, 3, 8, 3, 2
Offset: 0

Views

Author

G. C. Greubel, Dec 25 2015

Keywords

Examples

			-0.400319302807725593843580317520320367201261286266232944284106942....
		

Crossrefs

Cf. A075700 (zeta'(0)), A084448 (zeta'(-1)), A240966 (zeta'(-2)), A259068 (zeta'(-3)), A259069 (zeta'(-4)), A259070 (zeta'(-5)), A259071 (zeta'(-6)), A259072 (zeta'(-7)), A259073 (zeta'(-8)), A266260 (zeta'(-9)), A266261 (zeta'(-10)), A266262 (zeta'(-11)), A266263 (zeta'(-12)), A260660 (zeta'(-13)), A266264 (zeta'(-14)), A266271 (zeta'(-16)), A266272 (zeta'(-17)), A266273 (zeta'(-18)), A266274 (zeta'(-19)), A266275 (zeta'(-20)).

Programs

  • Mathematica
    RealDigits[N[Zeta'[-15], 100]]

Formula

zeta'(-n) = (BernoulliB(n+1)*HarmonicNumber(n))/(n+1) - log(A(n)), where A(n) is the n-th Bendersky constant.
zeta'(-15) = -4325053069/2940537600 - log(A(15)).

A266272 Decimal expansion of zeta'(-17) (the derivative of Riemann's zeta function at -17).

Original entry on oeis.org

3, 1, 2, 8, 6, 4, 5, 3, 3, 2, 1, 2, 4, 1, 5, 7, 8, 7, 5, 6, 8, 4, 4, 5, 2, 6, 3, 9, 1, 5, 3, 3, 3, 0, 5, 4, 8, 2, 2, 6, 3, 3, 9, 0, 7, 7, 5, 6, 5, 4, 7, 9, 7, 4, 2, 4, 9, 1, 6, 5, 7, 7, 0, 6, 1, 1, 4, 3, 4, 1, 1, 2, 9, 6, 9, 3, 4, 0, 0, 5, 3, 4, 7, 1, 1, 7, 3, 6, 2, 8, 6, 6, 6, 3
Offset: 1

Views

Author

G. C. Greubel, Dec 25 2015

Keywords

Examples

			3.1286453321241578756844526391533305482263390775654797424916577061....
		

Crossrefs

Cf. A075700 (zeta'(0)), A084448 (zeta'(-1)), A240966 (zeta'(-2)), A259068 (zeta'(-3)), A259069 (zeta'(-4)), A259070 (zeta'(-5)), A259071 (zeta'(-6)), A259072 (zeta'(-7)), A259073 (zeta'(-8)), A266260 (zeta'(-9)), A266261 (zeta'(-10)), A266262 (zeta'(-11)), A266263 (zeta'(-12)), A260660 (zeta'(-13)), A266264 (zeta'(-14)), A266270 (zeta'(-15)), A266271 (zeta'(-16)), A266273 (zeta'(-18)), A266274 (zeta'(-19)), A266275 (zeta'(-20)).

Programs

  • Mathematica
    RealDigits[N[Zeta'[-17], 100]]

Formula

zeta'(-n) = HarmonicNumber(n)*BernoulliB(n+1)/(n+1) - log(A(n)), where A(n) is the n-th Bendersky constant.
zeta'(-17) = 1848652896341/175991175360 - log(A(17)).

Extensions

Offset corrected by Rick L. Shepherd, May 21 2016

A266261 Decimal expansion of zeta'(-10) (the derivative of Riemann's zeta function at -10).

Original entry on oeis.org

0, 1, 8, 9, 2, 9, 9, 2, 6, 3, 3, 8, 1, 4, 0, 3, 7, 4, 2, 2, 8, 9, 8, 0, 5, 0, 2, 2, 9, 0, 3, 4, 6, 7, 9, 5, 2, 3, 1, 9, 8, 5, 2, 5, 8, 0, 9, 5, 1, 6, 9, 5, 5, 5, 8, 1, 0, 4, 8, 6, 2, 3, 1, 1, 0, 0, 7, 0, 2, 7, 0, 5, 1, 5, 5, 0, 4, 1, 4, 8, 0, 5, 5, 2, 3, 5, 1, 6, 0, 7, 3
Offset: 0

Views

Author

G. C. Greubel, Dec 25 2015

Keywords

Examples

			-0.0189299263381403742289805022903467952319852580951695558
		

Crossrefs

Cf. A075700 (zeta'(0)), A084448 (zeta'(-1)), A240966 (zeta'(-2)), A259068 (zeta'(-3)), A259070 (zeta'(-5)), A259071 (zeta'(-6)), A259072 (zeta'(-7)), A259073 (zeta'(-8)), A266260 (zeta'(-9)), A266262 (zeta'(-11)), A266263 (zeta'(-12)), A260660 (zeta'(-13)), A266264 (zeta'(-14)), A266270 (zeta'(-15)), A266271 (zeta'(-16)), A266272 (zeta'(-17)), A266273 (zeta'(-18)), A266274 (zeta'(-19)), A266275 (zeta'(-20)).

Programs

  • Mathematica
    Join[{0}, RealDigits[-(5/264)*(Zeta[11]/Zeta[10]), 10, 100] // First]

Formula

zeta'(-10) = -14175*zeta(11)/(8*Pi^10) = log(A(10)).
Equals -(5/264)*(zeta(11)/zeta(10)).

A266263 Decimal expansion of zeta'(-12) (the derivative of Riemann's zeta function at -12).

Original entry on oeis.org

0, 6, 3, 2, 7, 0, 5, 8, 3, 3, 4, 1, 4, 6, 3, 0, 0, 0, 5, 9, 5, 1, 8, 2, 3, 0, 1, 2, 3, 4, 3, 0, 7, 7, 6, 7, 5, 1, 1, 4, 1, 8, 1, 8, 4, 7, 5, 3, 2, 3, 6, 3, 7, 6, 6, 7, 9, 5, 6, 5, 9, 4, 5, 6, 7, 0, 6, 2, 1, 5, 2, 5, 4, 6, 0, 6, 7, 4, 9, 7, 6, 7, 3, 7, 4, 7, 1, 0, 3, 4, 3, 7, 1
Offset: 0

Views

Author

G. C. Greubel, Dec 25 2015

Keywords

Examples

			0.06327058334146300059518230123430776751141818475323637667956594567...
		

Crossrefs

Cf. A075700 (zeta'(0)), A084448 (zeta'(-1)), A240966 (zeta'(-2)), A259068 (zeta'(-3)), A259069 (zeta'(-4)), A259070 (zeta'(-5)), A259071 (zeta'(-6)), A259072 (zeta'(-7)), A259073 (zeta'(-8)), A266260 (zeta'(-9)), A266261 (zeta'(-10)), A266262 (zeta'(-11)), A260660 (zeta'(-13)), A266264 (zeta'(-14)), A266270 (zeta'(-15)), A266271 (zeta'(-16)), A266272 (zeta'(-17)), A266273 (zeta'(-18)), A266274 (zeta'(-19)), A266275 (zeta'(-20)).

Programs

  • Mathematica
    Join[{0}, RealDigits[(691/10920)*(Zeta[13]/Zeta[12]), 10, 100] // First]

Formula

zeta'(-12) = (-467775*Zeta(13))/(8*Pi^12) = - log(A(12)).
Equals (691/10920)*(zeta(13)/zeta(12)).

A266264 Decimal expansion of zeta'(-14) (the derivative of Riemann's zeta function at -14).

Original entry on oeis.org

2, 9, 1, 6, 5, 7, 7, 2, 4, 7, 4, 3, 8, 7, 3, 5, 2, 0, 3, 2, 1, 2, 2, 4, 0, 0, 3, 0, 7, 0, 2, 5, 0, 6, 6, 6, 9, 7, 0, 2, 6, 3, 0, 3, 8, 5, 3, 3, 0, 9, 0, 8, 3, 2, 1, 4, 9, 9, 0, 9, 3, 5, 9, 6, 5, 6, 5, 1, 5, 1, 8, 7, 0, 2, 8, 4, 6, 3, 7, 5, 8, 6, 7, 7, 5, 0, 9, 3, 9, 2, 4, 0, 9, 7, 2
Offset: 0

Views

Author

G. C. Greubel, Dec 25 2015

Keywords

Examples

			-0.29165772474387352032122400307025066697026303853309083214990....
		

Crossrefs

Cf. A075700 (zeta'(0)), A084448 (zeta'(-1)), A240966 (zeta'(-2)), A259068 (zeta'(-3)), A259069 (zeta'(-4)), A259070 (zeta'(-5)), A259071 (zeta'(-6)), A259072 (zeta'(-7)), A259073 (zeta'(-8)), A266260 (zeta'(-9)), A266261 (zeta'(-10)), A266262 (zeta'(-11)), A266263 (zeta'(-12)), A260660 (zeta'(-13)), A266270 (zeta'(-15)), A266271 (zeta'(-16)), A266272 (zeta'(-17)), A266273 (zeta'(-18)), A266274 (zeta'(-19)), A266275 (zeta'(-20)).

Programs

  • Mathematica
    RealDigits[N[Zeta'[-14], 100]]

Formula

zeta'(-14) = - (42567525*zeta(15))/(16*Pi^14) = - log(A(14)).
Equals -(7/24)*(zeta(15)/zeta(14)).
Showing 1-10 of 33 results. Next