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.

A128578 Main diagonal of table A128570.

Original entry on oeis.org

1, 2, 24, 580, 21420, 1068480, 67189248, 5098406400, 453030209280, 46120247659200, 5290918350734016, 675157532791996800, 94836990558591590400, 14538639675855504384000, 2415072877848471727687680
Offset: 0

Views

Author

Paul D. Hanna, Mar 11 2007

Keywords

Comments

Limit n->infinity (a(n)/n!)^(1/n) = 12.67567... . - Vaclav Kotesovec, Mar 19 2016

Crossrefs

Cf. A128570 (triangle), rows: A128318, A128571, A128572, A128573, A128574, A128575, A128576; A128577 (square of row 0), A128579 (antidiagonal sums).

Programs

  • PARI
    {a(n)=local(A=1+(2*n+1)*x); for(j=0,n,A=1+(2*n+1-j)*x*A^2 +x*O(x^n));polcoeff(A,n)}