%I A103257
%S A103257 1,2,4,6,10,14,20,28,40,54,72,96,126,164,212,272,346,436,548,684,850,
%T A103257 1052,1296,1588,1940,2362,2864,3462,4172,5012,6004,7172,8548,10160,
%U A103257 12048,14256,16830,19828,23312,27356,32040
%N A103257 Number of partitions of 2n free of multiples of 5. All odd parts occur
with multiplicity 2 or 4. the even parts occur at most twice.
%D A103257 N. Chair, Partition identities from partial supersymmetry.
%F A103257 G.f.: (theta_4(0, x^3)*theta_4(0, x^5))/theta_4(0, x).
%e A103257 E.g. a(10) = 14 because 10 can be written as 8+2 = 8+1+1 = 6+4 = 6+2+2
= 6+2+1+1 = 6+1+1+1+1 = 4+4+2 = 4+4+1+1 = 4+3+3 = 4+2+2+1+1 = 4+2+1+1+1+1
= 3+3+2+2 = 3+3+2+1+1 = 3+3+1+1+1+1.
%p A103257 series(product(((1+x^k)*(1-x^(3*k))*(1-x^(5*k)))/((1-x^k)*(1+x^(3*k))*(1-x^(5*k))),
k=1..100),x=0,100);
%Y A103257 Cf. A098151.
%Y A103257 Sequence in context: A088932 A088954 A000123 this_sequence A103259 A082380
A136460
%Y A103257 Adjacent sequences: A103254 A103255 A103256 this_sequence A103258 A103259
A103260
%K A103257 nonn
%O A103257 0,2
%A A103257 Noureddine Chair (n.chair(AT)rocketmail.com), Jan 27 2005
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