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.

A145085 Square table, read by antidiagonals, where row e.g.f.s, R(n,x), satisfy: d/dx log( R(n,x) ) = R(n+1,x)^(n+1) with R(n,0) = 1; that is, the logarithmic derivative of the e.g.f. of row n equals the e.g.f. of row n+1 to the n+1 power, for n>=0.

Original entry on oeis.org

1, 1, 1, 1, 1, 2, 1, 1, 3, 7, 1, 1, 4, 17, 39, 1, 1, 5, 31, 151, 322, 1, 1, 6, 49, 373, 1901, 3723, 1, 1, 7, 71, 741, 6250, 31851, 57577, 1, 1, 8, 97, 1291, 15457, 136711, 680265, 1147188, 1, 1, 9, 127, 2059, 32186, 416661, 3740137, 17947631, 28557909, 1, 1, 10, 161, 3081, 59677, 1030491, 13908049, 124143598, 571101141, 866222535
Offset: 0

Views

Author

Paul D. Hanna, Oct 01 2008

Keywords

Examples

			Table begins:
1,1,2,7,39,322,3723,57577,1147188,28557909,866222535,31362744620,...;
1,1,3,17,151,1901,31851,680265,17947631,571101141,21507723971,...;
1,1,4,31,373,6250,136711,3740137,124143598,4887140221,224203589593,...;
1,1,5,49,741,15457,416661,13908049,557865765,26296627233,...;
1,1,6,71,1291,32186,1030491,40606281,1911466016,105145651821,...;
1,1,7,97,2059,59677,2211823,100479577,5431432483,341787359269,...;
1,1,8,127,3081,101746,4283511,220384585,13453788426,953539677861,...;
1,1,9,161,4393,162785,7672041,440897697,30000376553,2365207145121,...;
1,1,10,199,6031,247762,12921931,820341289,61561430380,5344379824933,...;
1,1,11,241,8031,362221,20710131,1439328361,118089834231,11194348009941,...;
1,1,12,287,10429,512282,31860423,2405825577,214232473478,22019097106029,..;
1,1,13,337,13261,704641,47357821,3860734705,370824076621,41076472798081,..;
1,1,14,391,16563,946570,68362971,5983992457,616668950808,73237232298621,..;
		

Crossrefs

Programs

  • PARI
    {T(n,k)=local(A=vector(n+k+2,j,1+j*x)); for(i=0,n+k+1,for(j=0,n+k,m=n+k+1-j;A[m]=exp(intformal(A[m+1]^m+x*O(x^k))))); k!*polcoeff(A[n+1],k,x)}
    for(n=0, 10, for(k=0, 10, print1(T(n, k), ", ")); print(""))

Formula

Row e.g.f.s satisfy: R(n,x) = exp( Integral R(n+1,x)^(n+1) dx ).
Row e.g.f.s satisfy: R(n,x) = 1 + Integral R(n,x)*R(n+1,x)^(n+1) dx.
Row e.g.f.s satisfy: R'(n,x)/R(n,x) = R(n+1,x)^(n+1) with R(n,0) = 1.

Extensions

Entry corrected by Paul D. Hanna, Sep 22 2020