# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a110154 Showing 1-1 of 1 %I A110154 #3 Mar 30 2012 18:36:49 %S A110154 1,4,20,84,380,1540,6796,27380,117020,476260,2002220,8063316,33957180, %T A110154 136489156,566211660,2290272692,9463603036,38042178340,157211980652, %U A110154 631321594900,2594532576636,10457495255940,42791736547980 %N A110154 G.f.: A(x) = Product_{n>=1} 1/(1 - 4^n*x^n)^(4/4^n); self-convolution of A110156. %e A110154 A(x) = 1 + 4*x + 20*x^2 + 84*x^3 + 380*x^4 + 1540*x^5 +... = %e A110154 1/[(1-4*x)*(1-16*x^2)^(1/4)*(1-64*x^3)^(1/16)*(1-256*x^4)^(1/64)*...] %o A110154 (PARI) a(n)=polcoeff(prod(k=1,n,1/(1-4^k*x^k+x*O(x^n))^(4/4^k)),n) %Y A110154 Cf. A110152, A110153, A110155, A110156. %K A110154 nonn %O A110154 0,2 %A A110154 _Paul D. Hanna_, Jul 14 2005 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE