

A060426


a(n) is the number of degrees in the sequence of the degrees of the irreducible representations of the symmetric group S_n that appear only once.


1



1, 0, 1, 1, 1, 1, 1, 2, 1, 2, 2, 3, 2, 3, 4, 4, 5, 5, 4, 6, 8, 8, 6, 7, 10, 11, 11, 15, 15, 16, 18, 21, 22, 23, 29, 33, 31, 31, 39, 43, 44, 52, 51, 58, 64, 71, 66, 82, 88, 96, 93, 103, 115, 128, 143, 150, 156, 160, 173, 199, 202, 202, 242, 263, 269, 293, 308
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OFFSET

1,8


COMMENTS

Bounded above by A000700(n).  Eric M. Schmidt, Apr 29 2013


LINKS

Table of n, a(n) for n=1..67.


EXAMPLE

a(6) = 1 because the degrees for S_6 are 1,1,5,5,5,5,9,9,10,10,16 and the only number that appears once is 16.


PROG

(Sage)
def A060426(n) :
....mult = {}
....for P in Partitions(n) :
........dim = P.dimension()
........mult[dim] = mult.get(dim, 0) + 1
....return len([m for m in iter(mult) if mult[m]==1])
end; # Eric M. Schmidt, Apr 29 2013


CROSSREFS

Cf. A060437, A059867, A060368, A060369, A061569, A089248. [From M. F. Hasler, Jun 14 2009]
Sequence in context: A097575 A103273 A025066 * A260412 A283451 A172245
Adjacent sequences: A060423 A060424 A060425 * A060427 A060428 A060429


KEYWORD

nonn


AUTHOR

Avi Peretz (njk(AT)netvision.net.il), Apr 05 2001


EXTENSIONS

More terms from Eric M. Schmidt, Apr 29 2013


STATUS

approved



