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.

A260322 Triangle read by rows: T(n,k) = logarithmic polynomial G_k^(n)(x) evaluated at x=1.

Original entry on oeis.org

1, -1, 2, 2, -6, 6, 0, 24, -24, 24, 9, -80, 60, -120, 120, 35, 450, 240, 360, -720, 720, 230, -2142, -2310, -840, 2520, -5040, 5040, 1624, 17696, 9744, 21840, -6720, 20160, -40320, 40320, 13209, -112464, 91224, -184464, 15120, -60480, 181440, -362880, 362880
Offset: 1

Views

Author

N. J. A. Sloane, Jul 23 2015

Keywords

Examples

			Triangle begins:
    1;
   -1,     2;
    2,    -6,     6;
    0,    24,   -24,   24;
    9,   -80,    60, -120,  120;
   35,   450,   240,  360, -720,   720;
  230, -2142, -2310, -840, 2520, -5040, 5040;
  ...
		

Crossrefs

Rows, column sums give A002741, A002742, A002743, A002744.
Main diagonal gives A000142.

Programs

  • Maple
    A260322 := proc(n,r)
        if r = 0 then
            1 ;
        elif n > r+1 then
            0 ;
        else
            add( (-1)^(r-j*n)/(r-j*n)!/j,j=1..(r)/n) ;
            %*r! ;
        end if;
    end proc:
    for r from 1 to 20 do
        for n from 1 to r do
            printf("%a,",A260322(n,r)) ;
        end do:
        printf("\n") ;
    end do: # R. J. Mathar, Jul 24 2015
  • Mathematica
    T[n_, k_] := Which[n == 0, 1, k > n+1, 0, True,
       Sum[(-1)^(n-j*k)/(n-j*k)!/j, {j, 1, n/k}]] n!;
    Table[T[n, k], {n, 1, 9}, {k, 1, n}] // Flatten (* Jean-François Alcover, Apr 30 2023 *)