This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A111541 #5 Jun 13 2017 22:31:55 %S A111541 0,1,0,3,2,0,14,5,3,0,84,22,8,4,0,600,128,36,12,5,0,4908,896,212,58, %T A111541 17,6,0,44952,7220,1496,360,90,23,7,0,454344,65336,12128,2652,602,134, %U A111541 30,8,0,5016768,653720,110288,22320,4736,974,192,38,9,0,60062352,7155104 %N A111541 Matrix logarithm of triangle A111536. %C A111541 Column 0 (A111538) is found in column 2 of triangle A111536. %e A111541 Triangle begins: %e A111541 0; %e A111541 1,0; %e A111541 3,2,0; %e A111541 14,5,3,0; %e A111541 84,22,8,4,0; %e A111541 600,128,36,12,5,0; %e A111541 4908,896,212,58,17,6,0; %e A111541 44952,7220,1496,360,90,23,7,0; %e A111541 454344,65336,12128,2652,602,134,30,8,0; %e A111541 5016768,653720,110288,22320,4736,974,192,38,9,0; ... %o A111541 (PARI) T(n,k)=local(M=matrix(n+1,n+1,m,j,if(m==j,1,if(m==j+1,-m+1, -(m-j-1)*polcoeff(log(sum(i=0,m,(i+1)!/1!*x^i)),m-j-1))))); return(if(n<k || k<0,0,sum(i=1,#M,(M^0-M)^i/i)[n+1,k+1])) %Y A111541 Cf. A111536, A111538 (column 0), A111542 (column 1), A111543 (column 2). %K A111541 nonn,tabl %O A111541 0,4 %A A111541 _Paul D. Hanna_, Aug 06 2005