A135894 Triangle R, read by rows, where column k of R equals column 0 of P^(2k+1) where P=A135880.
1, 1, 1, 2, 3, 1, 6, 12, 5, 1, 25, 63, 30, 7, 1, 138, 421, 220, 56, 9, 1, 970, 3472, 1945, 525, 90, 11, 1, 8390, 34380, 20340, 5733, 1026, 132, 13, 1, 86796, 399463, 247066, 72030, 13305, 1771, 182, 15, 1, 1049546, 5344770, 3430936, 1028076, 194646, 26565, 2808
Offset: 0
Examples
Triangle R begins: 1; 1, 1; 2, 3, 1; 6, 12, 5, 1; 25, 63, 30, 7, 1; 138, 421, 220, 56, 9, 1; 970, 3472, 1945, 525, 90, 11, 1; 8390, 34380, 20340, 5733, 1026, 132, 13, 1; 86796, 399463, 247066, 72030, 13305, 1771, 182, 15, 1; 1049546, 5344770, 3430936, 1028076, 194646, 26565, 2808, 240, 17, 1; 14563135, 81097517, 53741404, 16477041, 3182778, 442948, 47801, 4185, 306, 19, 1; ... where column k of R equals column 0 of P^(2k+1) for k>=0, and P = A135880 begins: 1; 1, 1; 2, 2, 1; 6, 7, 3, 1; 25, 34, 15, 4, 1; 138, 215, 99, 26, 5, 1; 970, 1698, 814, 216, 40, 6, 1; ... where column k of P equals column 0 of R^(k+1). The matrix product P^-1*R = A135898 = P (shifted right one column); the matrix product R^-1*P^2 = A135900 = R (shifted down one row).
Crossrefs
Programs
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PARI
{T(n,k)=local(P=Mat(1),R=Mat(1),PShR);if(n>0,for(i=0,n, PShR=matrix(#P,#P, r,c, if(r>=c,if(r==c,1,if(c==1,0,P[r-1,c-1]))));R=P*PShR; R=matrix(#P+1, #P+1, r,c, if(r>=c, if(r<#P+1,R[r,c], if(c==1,(P^2)[ #P,1],(P^(2*c-1))[r-c+1,1])))); P=matrix(#R, #R, r,c, if(r>=c, if(r<#R,P[r,c], (R^c)[r-c+1,1])))));R[n+1,k+1]}
Formula
Extensions
Typo in formula corrected by Paul D. Hanna, Mar 26 2010
Comments