%I #9 Oct 15 2024 10:30:04
%S 1,5,35,385,7315,256025,17153675,2247131425,582007039075,
%T 299733625123625,307826433001962875,631352014087025856625,
%U 2587911905742718986305875,21207938067561582092776645625,347534481113131645754330891856875,11389052480558437163015177657041650625
%N (1/4) times obverse convolution (2)**(2^n + 1); see Comments.
%C See A374848 for the definition of obverse convolution and a guide to related sequences.
%F a(n) = a(n-1)*A062709(n) for n>=1.
%F a(n) = (1/4)((3)**(2^n)) = (1/4)(A010701(n)**A000079(n)) for n>=0.
%t s[n_] := 2; t[n_] := 2^n + 1;
%t u[n_] := (1/4) Product[s[k] + t[n - k], {k, 0, n}];
%t Table[u[n], {n, 0, 20}]
%t (* or *)
%t Table[2^(n*(n+1)/2 - 2) * QPochhammer[-3, 1/2, n+1], {n, 0, 15}] (* _Vaclav Kotesovec_, Sep 20 2024 *)
%Y Cf. A000051, A000079, A007395, A010701, A374848, A375054, A139030.
%K nonn,changed
%O 0,2
%A _Clark Kimberling_, Sep 20 2024