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 1-4 of 4 results.

A370472 G.f. satisfies A(x) = 1 + x * A(x) * (1 - A(x) + A(x)^2 - A(x)^3 + A(x)^4).

Original entry on oeis.org

1, 1, 3, 15, 88, 565, 3844, 27228, 198670, 1482981, 11271117, 86926262, 678568982, 5351340410, 42570335161, 341201704970, 2752693408051, 22335989938093, 182166978172055, 1492496248447713, 12278191839580716, 101382009468089580, 839932374157895727
Offset: 0

Views

Author

Seiichi Manyama, Mar 31 2024

Keywords

Crossrefs

Programs

  • PARI
    a(n) = sum(k=0, n, binomial(n, k)*binomial(n/2+5*k/2+1/2, n)/(n+5*k+1));

Formula

G.f. A(x) satisfies:
(1) A(x)^2 = 1 + x * A(x) * (1 + A(x)^5).
(2) A(x) = sqrt(B(x)) where B(x) is the g.f. of A370471.
a(n) = Sum_{k=0..n} binomial(n,k) * binomial(n/2+5*k/2+1/2,n)/(n+5*k+1).

A370475 G.f. satisfies A(x) = 1 + x * A(x)^(3/2) * (1 + A(x)^(5/2)).

Original entry on oeis.org

1, 2, 11, 86, 785, 7818, 82360, 902394, 10178528, 117402240, 1378372807, 16417823232, 197903156219, 2409689022268, 29593911665705, 366158474520010, 4559848894822462, 57109656154370922, 718896822713092457, 9090475112572839810, 115417175337050727590
Offset: 0

Views

Author

Seiichi Manyama, Mar 31 2024

Keywords

Crossrefs

Programs

  • PARI
    a(n) = sum(k=0, n, binomial(n, k)*binomial(3*n/2+5*k/2+1, n)/(3*n/2+5*k/2+1));

Formula

a(n) = Sum{k=0..n} binomial(n,k) * binomial(3*n/2+5*k/2+1,n)/(3*n/2+5*k/2+1).

A371723 G.f. satisfies A(x) = ( 1 + x * A(x)^(1/4) * (1 + A(x)^(5/4)) )^2.

Original entry on oeis.org

1, 4, 18, 100, 623, 4156, 29032, 209656, 1552535, 11724904, 89958000, 699213444, 5494103979, 43570067100, 348274269966, 2803139823512, 22698137859554, 184779492011244, 1511406790180350, 12415340284461312, 102377122022648745, 847144310799588732
Offset: 0

Views

Author

Seiichi Manyama, Apr 04 2024

Keywords

Crossrefs

Programs

  • PARI
    a(n) = 2*sum(k=0, n, binomial(n, k)*binomial(n/2+5*k/2+2, n)/(n/2+5*k/2+2));

Formula

G.f.: B(x)^4 where B(x) is the g.f. of A370472.
a(n) = 2 * Sum_{k=0..n} binomial(n,k) * binomial(n/2+5*k/2+2,n)/(n/2+5*k/2+2).

A371725 G.f. satisfies A(x) = ( 1 + x * A(x)^(1/5) * (1 + A(x)) )^(5/2).

Original entry on oeis.org

1, 5, 25, 145, 925, 6266, 44245, 322075, 2399725, 18211775, 140285018, 1093997085, 8620125925, 68523526635, 548867710575, 4425604018075, 35892727867805, 292604563615625, 2396375011877275, 19707111724556025, 162671328783723678, 1347313142469049275
Offset: 0

Views

Author

Seiichi Manyama, Apr 04 2024

Keywords

Crossrefs

Programs

  • PARI
    a(n) = sum(k=0, n, binomial(n, k)*binomial(n/2+5*k/2+5/2, n)/(n/5+k+1));

Formula

G.f.: B(x)^5 where B(x) is the g.f. of A370472.
a(n) = Sum_{k=0..n} binomial(n,k) * binomial(n/2+5*k/2+5/2,n)/(n/5+k+1).
Showing 1-4 of 4 results.