%I A145075
%S A145075 1,4,18,172,1881,25644,411488
%N A145075 a(n) = [x^(5^n)] Q(x,n)^(n+1) where Q(x,n) = Sum_{k=0..n} (x^(5^k) + 
               x^(2*5^k) + x^(3*5^k) + x^(4*5^k)) for n>=0.
%e A145075 a(n) equals the coefficient of x^(5^n) in Q(x,n)^(n+1) where
%e A145075 Q(x,n) = Sum_{k=0..n} (x^(5^k) + x^(2*5^k) + x^(3*5^k) + x^(4*5^k)) for 
               n>=0.
%o A145075 (PARI) {a(n,q=5)=local(Q=sum(j=0,n,(x^(q^j)-x^(q*q^j))/(1-x^(q^j)+O(x^(q^n+1)))));
               polcoeff(Q^(n+1),q^n)}
%Y A145075 Cf. A007178, A145073, A145074, A145076.
%Y A145075 Sequence in context: A054759 A007153 A156870 this_sequence A058924 A154731 
               A071173
%Y A145075 Adjacent sequences: A145072 A145073 A145074 this_sequence A145076 A145077 
               A145078
%K A145075 more,nonn
%O A145075 0,2
%A A145075 Paul D. Hanna (pauldhanna(AT)juno.com), Oct 09 2008