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 1-2 of 2 results.

A120607 G.f. satisfies: 37*A(x) = 36 + 81*x + A(x)^10, starting with [1,3,15].

Original entry on oeis.org

1, 3, 15, 270, 5505, 124818, 3028200, 76896180, 2018211930, 54311811330, 1490518569747, 41556060361920, 1173726329836125, 33513124885393020, 965755118941566180, 28051840723006217040, 820439774630057541690
Offset: 0

Views

Author

Paul D. Hanna, Jun 16 2006

Keywords

Comments

See comments in A120588 for conditions needed for an integer sequence to satisfy a functional equation of the form: r*A(x) = c + b*x + A(x)^n.

Examples

			A(x) = 1 + 3*x + 15*x^2 + 270*x^3 + 5505*x^4 + 124818*x^5 +...
A(x)^10 = 1 + 30*x + 555*x^2 + 9990*x^3 + 203685*x^4 + 4618266*x^5 +...

Crossrefs

Cf. A120588 - A120606.

Programs

  • Mathematica
    CoefficientList[1 + InverseSeries[Series[(1+37*x - (1+x)^10)/81, {x, 0, 20}], x], x] (* Vaclav Kotesovec, Nov 28 2017 *)
  • PARI
    {a(n)=local(A=1+3*x+15*x^2+x*O(x^n));for(i=0,n,A=A+(-37*A+36+81*x+A^10)/27);polcoeff(A,n)}

Formula

G.f.: A(x) = 1 + Series_Reversion((1+37*x - (1+x)^10)/81). Lagrange Inversion yields: G.f.: A(x) = Sum_{n>=0} C(9*n,n)/(8*n+1) * (36+81*x)^(8*n+1)/37^(9*n+1). - Paul D. Hanna, Jan 24 2008
a(n) ~ 3^(-1 + 4*n) * (-36 + 9*(37/10)^(10/9))^(1/2 - n) / (2^(5/9) * 5^(1/18) * 37^(4/9) * n^(3/2) * sqrt(Pi)). - Vaclav Kotesovec, Nov 28 2017

A120605 G.f. satisfies: 25*A(x) = 24 + 64*x + A(x)^9, starting with [1,4,36].

Original entry on oeis.org

1, 4, 36, 984, 31716, 1140552, 43895208, 1768717872, 73674176868, 3146885203432, 137085166193976, 6066992348458704, 272023207778276136, 12330039492509279184, 564072488005316830416, 26010805156782400648800
Offset: 0

Views

Author

Paul D. Hanna, Jun 16 2006

Keywords

Comments

See comments in A120588 for conditions needed for an integer sequence to satisfy a functional equation of the form: r*A(x) = c + b*x + A(x)^n.

Examples

			A(x) = 1 + 4*x + 36*x^2 + 984*x^3 + 31716*x^4 + 1140552*x^5 +...
A(x)^9 = 1 + 36*x + 900*x^2 + 24600*x^3 + 792900*x^4 + 28513800*x^5 +...

Crossrefs

Cf. A120588 - A120604, A120606, A120607.

Programs

  • Mathematica
    CoefficientList[1 + InverseSeries[Series[(1+25*x - (1+x)^9)/64, {x, 0, 20}], x], x] (* Vaclav Kotesovec, Nov 28 2017 *)
  • PARI
    {a(n)=local(A=1+4*x+36*x^2+x*O(x^n));for(i=0,n,A=A+(-25*A+24+64*x+A^9)/16);polcoeff(A,n)}

Formula

G.f.: A(x) = 1 + Series_Reversion((1+25*x - (1+x)^9)/64). Lagrange Inversion yields: G.f.: A(x) = Sum_{n>=0} C(9*n,n)/(8*n+1) * (24+64*x)^(8*n+1)/25^(9*n+1). - Paul D. Hanna, Jan 24 2008
a(n) ~ 4^(-1 + 3*n) * (-24 + 8*(5/3)^(9/4))^(1/2 - n) / (3^(1/8) * 5^(7/8) * n^(3/2) * sqrt(Pi)). - Vaclav Kotesovec, Nov 28 2017
Showing 1-2 of 2 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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