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Column 1 of triangle A209196.
1

%I #8 Oct 21 2024 17:28:46

%S 1,4,32,487,11113,335745,12607257,565877928,29553415078,1760584360722,

%T 117828762999498,8752769915058447,714626485356930711,

%U 63609663369881873031,6130647517448380412727,636052622643842997577302,70679525819378610579659532,8375262433274665594692923984

%N Column 1 of triangle A209196.

%C G.f. of A209196 is exp( Sum_{n>=1} x^n/n * Sum_{k=0..n} binomial(n^2, n*k) * y^k ).

%o (PARI) {a(n)=polcoeff(polcoeff(exp(sum(m=1,n,x^m/m*sum(j=0,m,binomial(m^2,m*j)*y^j))+x*O(x^n)),n,x),1,y)}

%o for(n=1,20,print1(a(n),", "))

%K nonn

%O 1,2

%A _Paul D. Hanna_, Mar 05 2012