OFFSET
0,2
FORMULA
The convolution cube-root yields A202943.
EXAMPLE
G.f.: A(x) = 1 + 3*x + 24*x^2 + 640*x^3 + 61440*x^4 + 22020096*x^5 +...
where
A(x) = 1 + 3*x + 6*2^2*x^2 + 10*2^6*x^3 + 15*2^12*x^4 + 21*2^20*x^5 +...
Note that the cube root of the g.f. is an integer series:
A(x)^(1/3) = 1 + x + 7*x^2 + 199*x^3 + 20026*x^4 + 7296946*x^5 +...+ A202943(n)*x^n +...
PROG
(PARI) {a(n)=polcoeff(sum(m=0, n, (m+1)*(m+2)/2*2^(m*(m-1))*x^m+x*O(x^n)), n)}
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Dec 26 2011
STATUS
approved