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.

A304320 Table of coefficients in row functions R(n,x) such that [x^k] exp( k^n * x ) / R(n,x) = 0 for k>=1 and n>=1.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 1, 5, 1, 1, 1, 25, 54, 1, 1, 1, 113, 2317, 935, 1, 1, 1, 481, 76446, 466241, 22417, 1, 1, 1, 1985, 2246281, 153143499, 162016980, 685592, 1, 1, 1, 8065, 62861994, 43087884081, 673638499100, 85975473871, 25431764, 1, 1, 1, 32513, 1723380877, 11442690973075, 2331601789103231, 5510097691767062, 64545532370208, 1106630687, 1, 1, 1, 130561, 46836819846, 2972352315820441, 7570836550478960487, 287133439746933073357, 75312181798660695788, 65062315637060121, 55174867339, 1
Offset: 1

Views

Author

Paul D. Hanna, May 11 2018

Keywords

Comments

It is striking that the coefficients in this table consist entirely of integers.

Examples

			This table begins:
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, ...;
1, 1, 5, 54, 935, 22417, 685592, 25431764, 1106630687, 55174867339, ...;
1, 1, 25, 2317, 466241, 162016980, 85975473871, 64545532370208, ...;
1, 1, 113, 76446, 153143499, 673638499100, 5510097691767062, ...;
1, 1, 481, 2246281, 43087884081, 2331601789103231, 287133439746933073357, ...;
1, 1, 1985, 62861994, 11442690973075, 7570836550478960487, ...;
1, 1, 8065, 1723380877, 2972352315820441, 24013530904194819396970, ...;
1, 1, 32513, 46836819846, 765428206086770699, 75487364859452767380638650, ...;
1, 1, 130561, 1268169652561, 196425341268811084961, 236460748444613412476233431261, ...; ...
Let R(n,x) denote the o.g.f. of row n of this table, then the coefficient of x^k in exp(k^n*x)/R(n,x) = 0 for k>=1 and n>=1.
		

Crossrefs

Cf. A304321, A304322 (row 2), A304323 (row 3), A304324 (row 4), A304325 (row 5), A337551 (diagonal).

Programs

  • PARI
    {T(n,k) = my(A=[1],m); for(i=1, k, A=concat(A, 0); m=#A; A[m] = Vec( exp(x*(m-1)^n +x*O(x^m)) / Ser(A) )[m] ); A[k+1]}
    /* Print table: */
    for(n=1,8, for(k=0,8, print1( T(n,k),", "));print(""))
    /* Print as a flattened table: */
    for(n=0,10, for(k=0,n, print1( T(n-k+1,k),", "));)

Formula

For fixed row r > 1 is a(n) ~ sqrt(1-c) * r^(r*n) * n^((r-1)*n - 1/2) / (sqrt(2*Pi) * c^n * (r-c)^((r-1)*n) * exp((r-1)*n)), where c = -LambertW(-r*exp(-r)). - Vaclav Kotesovec, Aug 31 2020