login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A060368
Number of irreducible representations of the symmetric group S_n that have even degree.
2
0, 0, 1, 1, 3, 3, 7, 14, 22, 26, 40, 45, 69, 71, 112, 215, 281, 353, 458, 563, 728, 874, 1127, 1447, 1830, 2180, 2754, 3206, 4053, 4580, 5818, 8317, 10111, 12246, 14819, 17849, 21509, 25759, 30929, 37082, 44327, 52662, 62749, 74151, 88110, 103510, 122706
OFFSET
1,5
LINKS
FORMULA
The total number of irreducible representations of S_n is the partition function p(n) (sequence A000041) and the number of irreducible representations of the symmetric group S_n that have odd degree is given in A059867 so a(n) = A000041(n) - A059867(n) for n >= 1
EXAMPLE
a(3) = 1 because the degrees of the irreducible representations of S_3 are 1,1,2.
PROG
(Sage) def A060368(n) : dig = n.digits(2); return Partitions(n).cardinality() - prod(2^n for n in range(len(dig)) if dig[n]==1) # Eric M. Schmidt, Apr 29 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Avi Peretz (njk(AT)netvision.net.il), Apr 01 2001
EXTENSIONS
More terms from Eric M. Schmidt, Apr 29 2013
STATUS
approved