Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #5 Jun 14 2017 00:16:16
%S 1,5,35,485,15200,1144664,215155493,103674882878,130648799730635,
%T 437302448840089232,3936208033244539574405,96244898501021613327012635,
%U 6446494058446469307795159512465,1191218783863555524342034469450207222
%N Column 4 of table A125800; also equals row sums of matrix power A078122^4.
%C Triangle A078122 shifts left one column under matrix cube and is related to partitions into powers of 3.
%o (PARI) a(n)=local(p=4,q=3,A=Mat(1), B); for(m=1, n+1, B=matrix(m, m); for(i=1, m, for(j=1, i, if(j==i || j==1, B[i, j]=1, B[i, j]=(A^q)[i-1, j-1]); )); A=B); return(sum(c=0,n,(A^p)[n+1,c+1]))
%Y Cf. A125800, A078122; other columns: A078125, A078124, A125801, A125803.
%K nonn
%O 0,2
%A _Paul D. Hanna_, Dec 10 2006