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A061569
Number of irreducible representations of the symmetric group S_n such that their degree is divisible by 3.
2
0, 0, 0, 2, 1, 2, 6, 4, 21, 33, 38, 50, 74, 81, 95, 150, 135, 331, 436, 519, 630, 840, 931, 1089, 1472, 1464, 2983, 3691, 4511, 5523, 6761, 8187, 9900, 12067, 14397, 17734, 21394, 25529, 30456, 36609, 43125, 50987, 61074, 70801, 87676, 104100, 121838, 142899
OFFSET
1,4
COMMENTS
The total number of irreducible representations of S_n is the partition function partition(n) (sequence A000041) and the number of irreducible representations of the symmetric group S_n with their degree not divisible by 3 is given in A060840 so a(n) = A000041(n) - A060840(n).
LINKS
EXAMPLE
a(3) = 0 because the degrees of the irreducible representations of S_3 are 1,1,2.
PROG
(Sage) def A061569(n) : dig = n.digits(3); return Partitions(n).cardinality() - prod([1, 3^m, 3^m*(3^m+3)//2][dig[m]] for m in range(len(dig))) # Eric M. Schmidt, Apr 30 2013
CROSSREFS
Sequence in context: A343383 A151962 A072137 * A294523 A286651 A324342
KEYWORD
nonn
AUTHOR
Ola Veshta (olaveshta(AT)my-deja.com), May 18 2001
EXTENSIONS
More terms from Eric M. Schmidt, Apr 30 2013
STATUS
approved