%I A060840
%S A060840 1,2,3,3,6,9,9,18,9,9,18,27,27,54,81,81,162,54,54,108,162,162,324,486,
%T A060840 486,972,27,27,54,81,81,162,243,243,486,243,243,486,729,729,1458,2187,
%U A060840 2187,4374,1458,1458,2916,4374,4374,8748,13122,13122,26244,405,405,810
%N A060840 Number of irreducible representations of symmetric group S_n whose degree 
               is not divisible by 3.
%D A060840 I. G. MacDonald, On the degrees of the irreducible representations of 
               symmetric groups, Bull. London Math. Soc. 3 (1971), 189-192
%F A060840 If n = sum a_i*3^e[i] in base 3 where a_i is 0, 1, 2 then a(n) = product 
               g(i) where if a(i) = 0 g(i) = 1, if a(i) = 1 g(i) = 3^i, if a(i) 
               = 2 g(i) = 3^i * (3^i + 3) / 2
%e A060840 a(4) = 3 because the degrees for S_4 are 1,1,2,3,3 and by the formula: 
               4 in base 3 is 11 and a(4) = 1*3
%Y A060840 A059867.
%Y A060840 Sequence in context: A020878 A158278 A027100 this_sequence A074717 A129068 
               A079888
%Y A060840 Adjacent sequences: A060837 A060838 A060839 this_sequence A060841 A060842 
               A060843
%K A060840 nonn,easy
%O A060840 1,2
%A A060840 Noam Katz (noamkj(AT)hotmail.com), May 02 2001
%E A060840 More terms from Larry Reeves (larryr(AT)acm.org), May 10 2001