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A145515 Square array A(n,k), n>=0, k>=0, read by antidiagonals: A(n,k) is the number of partitions of k^n into powers of k. 18
1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 4, 1, 1, 1, 2, 5, 10, 1, 1, 1, 2, 6, 23, 36, 1, 1, 1, 2, 7, 46, 239, 202, 1, 1, 1, 2, 8, 82, 1086, 5828, 1828, 1, 1, 1, 2, 9, 134, 3707, 79326, 342383, 27338, 1, 1, 1, 2, 10, 205, 10340, 642457, 18583582, 50110484, 692004, 1, 1, 1, 2, 11, 298, 24901, 3649346, 446020582, 14481808030, 18757984046, 30251722, 1, 1 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,8

LINKS

Alois P. Heinz, Table of n, a(n) for n = 0..860

FORMULA

See program.

For k>1: A(n,k) = [x^(k^n)] 1/Product_{j>=0}(1-x^(k^j)).

EXAMPLE

A(2,3) = 5, because there are 5 partitions of 3^2=9 into powers of 3: [1,1,1,1,1,1,1,1,1], [1,1,1,1,1,1,3], [1,1,1,3,3], [3,3,3], [9].

Square array A(n,k) begins:

1,  1,   1,    1,     1,      1,  ...

1,  1,   2,    2,     2,      2,  ...

1,  1,   4,    5,     6,      7,  ...

1,  1,  10,   23,    46,     82,  ...

1,  1,  36,  239,  1086,   3707,  ...

1,  1, 202, 5828, 79326, 642457,  ...

MAPLE

b:= proc(n, j, k) local nn;

      nn:= n+1;

      if n<0  then 0

    elif j=0  or n=0 or k<=1 then 1

    elif j=1  then nn

    elif n>=j then (nn-j) *binomial(nn, j) *add (binomial(j, h)

                   /(nn-j+h) *b(j-h-1, j, k) *(-1)^h, h=0..j-1)

              else b(n, j, k):= b(n-1, j, k) +b(k*n, j-1, k)

      fi

    end:

A:= (n, k)-> b(1, n, k):

seq (seq (A(n, d-n), n=0..d), d=0..13);

CROSSREFS

Columns 0+1, 2-10 give: A000012, A002577, A078125, A078537, A111822, A111827, A111832, A111837, A145512, A145513. Diagonal gives: A145514. Row 3 gives: A189890(k+1). Cf. A007318.

Sequence in context: A129176 A134132 A030424 * A188919 A026519 A025177

Adjacent sequences:  A145512 A145513 A145514 * A145516 A145517 A145518

KEYWORD

nonn,tabl

AUTHOR

Alois P. Heinz (heinz(AT)hs-heilbronn.de), Oct 11 2008

EXTENSIONS

Edited by Alois P. Heinz (heinz(AT)hs-heilbronn.de), Jan 12 2011

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Last modified February 15 21:02 EST 2012. Contains 205852 sequences.