%I #3 Mar 30 2012 18:36:49

%S 1,4,20,84,380,1540,6796,27380,117020,476260,2002220,8063316,33957180,

%T 136489156,566211660,2290272692,9463603036,38042178340,157211980652,

%U 631321594900,2594532576636,10457495255940,42791736547980

%N G.f.: A(x) = Product_{n>=1} 1/(1 - 4^n*x^n)^(4/4^n); self-convolution of A110156.

%e A(x) = 1 + 4*x + 20*x^2 + 84*x^3 + 380*x^4 + 1540*x^5 +... =

%e 1/[(1-4*x)*(1-16*x^2)^(1/4)*(1-64*x^3)^(1/16)*(1-256*x^4)^(1/64)*...]

%o (PARI) a(n)=polcoeff(prod(k=1,n,1/(1-4^k*x^k+x*O(x^n))^(4/4^k)),n)

%Y Cf. A110152, A110153, A110155, A110156.

%K nonn

%O 0,2

%A _Paul D. Hanna_, Jul 14 2005