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 16 results. Next

A157134 G.f. satisfies: A(x) = Sum_{n>=0} x^(n^2) * A(x)^n.

Original entry on oeis.org

1, 1, 1, 1, 2, 4, 7, 11, 18, 33, 63, 117, 211, 383, 713, 1348, 2547, 4793, 9039, 17165, 32785, 62761, 120243, 230768, 444119, 857015, 1656931, 3207990, 6219994, 12079544, 23496417, 45767352, 89256038, 174269488, 340646238, 666604642
Offset: 0

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Author

Paul D. Hanna, Feb 24 2009

Keywords

Examples

			G.f.: A(x) = 1 + x + x^2 + x^3 + 2*x^4 + 4*x^5 + 7*x^6 + 11*x^7 +...
A(x)^2 = 1 + 2*x + 3*x^2 + 4*x^3 + 7*x^4 + 14*x^5 + 27*x^6 +...
A(x)^3 = 1 + 3*x + 6*x^2 + 10*x^3 + 18*x^4 + 36*x^5 + 73*x^6 +...
A(x)^4 = 1 + 4*x + 10*x^2 + 20*x^3 + 39*x^4 + 80*x^5 + 168*x^6 +...
where
A(x) = 1 + x*A(x) + x^4*A(x)^2 + x^9*A(x)^3 + x^16*A(x)^4 +...
		

Crossrefs

Cf. A107595. [From Paul D. Hanna, Apr 25 2010]

Programs

  • PARI
    {a(n)=local(A=1+x+x*O(x^n));for(i=1,n,(A=sum(m=0,sqrtint(n),x^(m^2)*A^m)));polcoeff(A,n)}

Formula

G.f. satisfies: A(x) = B(x/A(x)) where B(x) = A(x*B(x)) = g.f. of A157135,
where A157135(n) = [x^n] A(x)^(n+1)/(n+1) for n>=0,
and a(n) = [x^n] -1/B(x)^(n-1)/(n-1) for n>1.
From Paul D. Hanna, Apr 25 2010: (Start)
G.f. A(x) satisfies the continued fraction:
A(x) = 1/(1- x*A(x)/(1- (x^3-x)*A(x)/(1- x^5*A(x)/(1- (x^7-x^3)*A(x)/(1- x^9*A(x)/(1- (x^11-x^5)*A(x)/(1- x^13*A(x)/(1- (x^15-x^7)*A(x)/(1- ...)))))))))
due to an identity of a partial elliptic theta function.
(End)
From Paul D. Hanna, May 05 2010: (Start)
Let A = g.f. A(x) at x=q, then A satisfies the q-series:
A = Sum_{n>=0} q^n*A^n*Product_{k=1..n} (1-q^(4k-3)*A)/(1-q^(4k-1)*A).
(End)

Extensions

Typo in data corrected by D. S. McNeil, Aug 17 2010

A176719 G.f. satisfies: A(x) = 1 + Sum_{n>=1} 2*x^n * A(x)^(n^2).

Original entry on oeis.org

1, 2, 6, 30, 194, 1442, 11782, 103102, 951554, 9173186, 91780614, 948985822, 10110931650, 110794764642, 1247186300934, 14412811665278, 170949340705794, 2081185257723778, 26012832364535814, 333929563132811678, 4404347475363755714, 59705917899701420834, 832080588205468939782
Offset: 0

Views

Author

Paul D. Hanna, Apr 25 2010

Keywords

Examples

			G.f.: A(x) = 1 + 2*x + 6*x^2 + 30*x^3 + 194*x^4 + 1442*x^5 +...
A(x) = 1 + 2*x*A(x) + 2*x^2*A(x)^4 + 2*x^3*A(x)^9 + 2*x^4*A(x)^16 + ...
Contribution from _Paul D. Hanna_, May 11 2010: (Start)
Given g.f. A(x), then Q = A(-x^2) satisfies the q-series:
Q/(1-x) = 1 + x*(xQ;Q)_1/(-xQ;Q)_1 + x^2*(xQ;Q)_2/(-xQ;Q)_2 +...
where the q-Pochhammer symbol (x;q)_n = Product_{k=0..n-1} (1-x*q^k). (End)
		

Crossrefs

Programs

  • PARI
    {a(n)=local(A=1+x);for(i=1,n,A=1+sum(m=1,n,2*x^m*(A+x*O(x^n))^(m^2)));polcoeff(A,n)}
    for(n=0,25,print1(a(n),", "))

Formula

Contribution from Paul D. Hanna, May 11 2010: (Start)
Given g.f. A(x), then Q = A(-x^2) satisfies:
Q = (1-x)*Sum_{n>=0} x^n*Product_{k=1..n} (1 - x*Q^k)/(1 + x*Q^k)
due to a q-series expansion for the Jacobi theta_4 function. (End)

Extensions

Edited by Paul D. Hanna, Apr 27 2010

A191803 G.f. satisfies: A(x) = Sum_{n>=0} x^n*A(x)^(5*n^2).

Original entry on oeis.org

1, 1, 6, 61, 791, 11701, 188462, 3225915, 57840755, 1076423857, 20666351126, 407645638428, 8237858879315, 170229866493435, 3592746391559133, 77393340642273491, 1701286171473636404, 38169860244429063080
Offset: 0

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Author

Paul D. Hanna, Jun 16 2011

Keywords

Examples

			G.f.: A(x) = 1 + x + 6*x^2 + 61*x^3 + 791*x^4 + 11701*x^5 + 188462*x^6 +...
where the g.f. satisfies:
A(x) = 1 + x*A(x)^5 + x^2*A(x)^20 + x^3*A(x)^45 + x^4*A(x)^80 +...+ x^n*A(x)^(5*n^2) +...
		

Crossrefs

Programs

  • PARI
    {a(n)=local(A=1+x);for(i=1,n,A=1+sum(m=1,n,x^m*(A+x*O(x^n))^(5*m^2)));polcoeff(A,n)}

Formula

Let A = g.f. A(x), then A satisfies:
(1) A = Sum_{n>=0} x^n*A^(5*n)*Product_{k=1..n} (1-x*A^(20*k-15))/(1-x*A^(20*k-5));
(2) A = 1/(1- A^5*x/(1- A^5*(A^10-1)*x/(1- A^25*x/(1- A^15*(A^20-1)*x/(1- A^45*x/(1- A^25*(A^30-1)*x/(1- A^65*x/(1- A^35*(A^40-1)*x/(1- ...))))))))) (continued fraction);
due to a q-series identity and an identity of a partial elliptic theta function, respectively.

A191800 G.f. satisfies: A(x) = Sum_{n>=0} x^n*A(x)^(2*n^2).

Original entry on oeis.org

1, 1, 3, 16, 109, 851, 7275, 66393, 637239, 6371848, 65961782, 703953599, 7722738071, 86924392498, 1002603956938, 11842465020207, 143208130730229, 1773099186411938, 22483740028949531, 292129222113885503, 3891268435685371911
Offset: 0

Views

Author

Paul D. Hanna, Jun 16 2011

Keywords

Examples

			G.f.: A(x) = 1 + x + 3*x^2 + 16*x^3 + 109*x^4 + 851*x^5 + 7275*x^6 +...
where the g.f. satisfies:
A(x) = 1 + x*A(x)^2 + x^2*A(x)^8 + x^3*A(x)^18 + x^4*A(x)^32 +...+ x^n*A(x)^(2*n^2) +...
		

Crossrefs

Programs

  • PARI
    {a(n)=local(A=1+x);for(i=1,n,A=1+sum(m=1,n,x^m*(A+x*O(x^n))^(2*m^2)));polcoeff(A,n)}

Formula

Let A = g.f. A(x), then A satisfies:
(1) A = Sum_{n>=0} x^n*A^(2*n)*Product_{k=1..n} (1-x*A^(8*k-6))/(1-x*A^(8*k-2));
(2) A = 1/(1- A^2*x/(1- A^2*(A^4-1)*x/(1- A^10*x/(1- A^6*(A^8-1)*x/(1- A^18*x/(1- A^10*(A^12-1)*x/(1- A^26*x/(1- A^14*(A^16-1)*x/(1- ...))))))))) (continued fraction);
due to a q-series identity and an identity of a partial elliptic theta function, respectively.

A191801 G.f. satisfies: A(x) = Sum_{n>=0} x^n*A(x)^(3*n^2).

Original entry on oeis.org

1, 1, 4, 28, 251, 2573, 28813, 343833, 4308210, 56154805, 756731761, 10499096630, 149551069156, 2182935186698, 32613646656198, 498420592612153, 7790219357236805, 124545937719356873, 2037614647316548891, 34134979366157116560
Offset: 0

Views

Author

Paul D. Hanna, Jun 16 2011

Keywords

Examples

			G.f.: A(x) = 1 + x + 4*x^2 + 28*x^3 + 251*x^4 + 2573*x^5 + 28813*x^6 +...
where the g.f. satisfies:
A(x) = 1 + x*A(x)^3 + x^2*A(x)^12 + x^3*A(x)^27 + x^4*A(x)^48 +...+ x^n*A(x)^(3*n^2) +...
		

Crossrefs

Programs

  • PARI
    {a(n)=local(A=1+x);for(i=1,n,A=1+sum(m=1,n,x^m*(A+x*O(x^n))^(3*m^2)));polcoeff(A,n)}

Formula

Let A = g.f. A(x), then A satisfies:
(1) A = Sum_{n>=0} x^n*A^(3*n)*Product_{k=1..n} (1-x*A^(12*k-9))/(1-x*A^(12*k-3));
(2) A = 1/(1- A^3*x/(1- A^3*(A^6-1)*x/(1- A^15*x/(1- A^9*(A^12-1)*x/(1- A^27*x/(1- A^15*(A^18-1)*x/(1- A^39*x/(1- A^21*(A^24-1)*x/(1- ...))))))))) (continued fraction);
due to a q-series identity and an identity of a partial elliptic theta function, respectively.

A191802 G.f. satisfies: A(x) = Sum_{n>=0} x^n*A(x)^(4*n^2).

Original entry on oeis.org

1, 1, 5, 43, 473, 5942, 81393, 1186342, 18132473, 287948903, 4722077279, 79636530163, 1377304530677, 24382127678100, 441294262119031, 8160739579770316, 154169018332135841, 2975846752734820345, 58718914018159811186
Offset: 0

Views

Author

Paul D. Hanna, Jun 16 2011

Keywords

Examples

			G.f.: A(x) = 1 + x + 5*x^2 + 43*x^3 + 473*x^4 + 5942*x^5 + 81393*x^6 +...
where the g.f. satisfies:
A(x) = 1 + x*A(x)^4 + x^2*A(x)^16 + x^3*A(x)^36 + x^4*A(x)^64 +...+ x^n*A(x)^(4*n^2) +...
		

Crossrefs

Programs

  • PARI
    {a(n)=local(A=1+x);for(i=1,n,A=1+sum(m=1,n,x^m*(A+x*O(x^n))^(4*m^2)));polcoeff(A,n)}

Formula

Let A = g.f. A(x), then A satisfies:
(1) A = Sum_{n>=0} x^n*A^(4*n)*Product_{k=1..n} (1-x*A^(16*k-12))/(1-x*A^(16*k-4));
(2) A = 1/(1- A^4*x/(1- A^4*(A^8-1)*x/(1- A^20*x/(1- A^12*(A^16-1)*x/(1- A^36*x/(1- A^20*(A^24-1)*x/(1- A^52*x/(1- A^28*(A^32-1)*x/(1- ...))))))))) (continued fraction);
due to a q-series identity and an identity of a partial elliptic theta function, respectively.

A191804 G.f. satisfies: A(x) = Sum_{n>=0} x^n*A(x)^(6*n^2).

Original entry on oeis.org

1, 1, 7, 82, 1221, 20718, 382315, 7489683, 153551487, 3264643144, 71545452946, 1609541143713, 37065029428453, 872037022019930, 20935244357544798, 512498682139660135, 12790021472251565047, 325439165493879484025
Offset: 0

Views

Author

Paul D. Hanna, Jun 16 2011

Keywords

Examples

			G.f.: A(x) = 1 + x + 7*x^2 + 82*x^3 + 1221*x^4 + 20718*x^5 + 382315*x^6 +...
where the g.f. satisfies:
A(x) = 1 + x*A(x)^6 + x^2*A(x)^24 + x^3*A(x)^54 + x^4*A(x)^96 +...+ x^n*A(x)^(6*n^2) +...
		

Crossrefs

Programs

  • PARI
    {a(n)=local(A=1+x);for(i=1,n,A=1+sum(m=1,n,x^m*(A+x*O(x^n))^(6*m^2)));polcoeff(A,n)}

Formula

Let A = g.f. A(x), then A satisfies:
(1) A = Sum_{n>=0} x^n*A^(6*n)*Product_{k=1..n} (1-x*A^(24*k-18))/(1-x*A^(24*k-6));
(2) A = 1/(1- A^6*x/(1- A^6*(A^12-1)*x/(1- A^30*x/(1- A^18*(A^24-1)*x/(1- A^54*x/(1- A^30*(A^36-1)*x/(1- A^78*x/(1- A^42*(A^48-1)*x/(1- ...))))))))) (continued fraction);
due to a q-series identity and an identity of a partial elliptic theta function, respectively.

A301929 G.f. A(x) satisfies: x = Sum_{n>=1} (1+x)^(n^2) * x^n / A(x)^n.

Original entry on oeis.org

1, 2, 3, 5, 12, 37, 138, 595, 2843, 14844, 83212, 496473, 3128584, 20707672, 143342216, 1034075244, 7752274237, 60251286521, 484483164365, 4023459643530, 34455215830001, 303839675537827, 2755675307738286, 25675275100067189, 245502965520844801, 2406797239543382867, 24170220195274548727, 248441483165679473094, 2611787614440970964621
Offset: 0

Views

Author

Paul D. Hanna, May 04 2018

Keywords

Examples

			G.f.: A(x) = 1 + 2*x + 3*x^2 + 5*x^3 + 12*x^4 + 37*x^5 + 138*x^6 + 595*x^7 + 2843*x^8 + 14844*x^9 + 83212*x^10 + 496473*x^11 + 3128584*x^12 + ...
such that
x = (1+x)*x/A(x) + (1+x)^4*x^2/A(x)^2 + (1+x)^9*x^3/A(x)^3 + (1+x)^16*x^4/A(x)^4 + (1+x)^25*x^5/A(x)^5 + (1+x)^36*x^6/A(x)^6 + (1+x)^49*x^7/A(x)^7 + ...
		

Crossrefs

Programs

  • PARI
    {a(n) = my(A=[1]); for(i=1, n, A = concat(A, 0); A[#A] = Vec(sum(n=0, #A, ((1+x)^n +x*O(x^#A))^n * x^n/Ser(A)^n ) )[#A+1] ); A[n+1]}
    for(n=0, 30, print1(a(n), ", "))

Formula

G.f.: x = Sum_{n>=1} x^n/A(x)^n * (1+x)^n * Product_{k=1..n} (A(x) - x*(1+x)^(4*k-3)) / (A(x) - x*(1+x)^(4*k-1)), due to a q-series identity.
G.f.: 1+x = 1/(1 - q*x/(A(x) - q*(q^2-1)*x/(1 - q^5*x/(A(x) - q^3*(q^4-1)*x/(1 - q^9*x/(A(x) - q^5*(q^6-1)*x/(1 - q^13*x/(A(x) - q^7*(q^8-1)*x/(1 - ...))))))))), where q = (1+x), a continued fraction due to a partial elliptic theta function identity.

A191805 G.f. satisfies: A(x) = Sum_{n>=0} x^n*A(x)^(n^3).

Original entry on oeis.org

1, 1, 2, 11, 83, 809, 9503, 130107, 2056768, 37137351, 761543233, 17637050418, 458225405825, 13265643258608, 424971569670808, 14963974979730138, 575619170223815326, 24056794697473352763, 1087014831018615150024
Offset: 0

Views

Author

Paul D. Hanna, Jun 16 2011

Keywords

Examples

			G.f.: A(x) = 1 + x + 2*x^2 + 11*x^3 + 83*x^4 + 809*x^5 + 9503*x^6 +...
where the g.f. satisfies:
A(x) = 1 + x*A(x) + x^2*A(x)^8 + x^3*A(x)^27 + x^4*A(x)^64 + x^5*A(x)^125 + x^6*A(x)^216 +...+ x^n*A(x)^(n^3) +...
		

Crossrefs

Programs

  • PARI
    {a(n)=local(A=1+x);for(i=1,n,A=1+sum(m=1,n,x^m*(A+x*O(x^n))^(m^3)));polcoeff(A,n)}

A191806 G.f. satisfies: A(x) = Sum_{n>=0} x^n*A(x)^(n^4).

Original entry on oeis.org

1, 1, 2, 19, 253, 5256, 153121, 5793349, 292530822, 18658710139, 1476004466687, 143228682526672, 16603062548806759, 2272210780577578355, 363396388117576899042, 67028665570181029621005, 14142153576677394736652147
Offset: 0

Views

Author

Paul D. Hanna, Jun 16 2011

Keywords

Examples

			G.f.: A(x) = 1 + x + 2*x^2 + 19*x^3 + 253*x^4 + 5256*x^5 + 153121*x^6 +...
where the g.f. satisfies:
A(x) = 1 + x*A(x) + x^2*A(x)^16 + x^3*A(x)^81 + x^4*A(x)^256 + x^5*A(x)^625 + x^6*A(x)^1296 +...+ x^n*A(x)^(n^4) +...
		

Crossrefs

Programs

  • PARI
    {a(n)=local(A=1+x);for(i=1,n,A=1+sum(m=1,n,x^m*(A+x*O(x^n))^(m^4)));polcoeff(A,n)}
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