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A113367
Column 2 of triangle A113365, also equals column 1 of A113340^6.
2
1, 18, 297, 5349, 109095, 2529909, 66345668, 1951815218, 63879120597, 2307569048308, 91351738972187, 3937843359099176, 183778364128820499, 9238674078250458082, 497996763423626058847, 28666454637876852704364
OFFSET
0,2
COMMENTS
A113365 equals the matrix cube of A113350, where column 2 of A113350^3 = column 1 of A113340^6.
PROG
(PARI) a(n)=local(A, B); A=matrix(1, 1); A[1, 1]=1; for(m=2, n+3, B=matrix(m, m); for(i=1, m, for(j=1, i, if(i<3 || j==i || j>m-1, B[i, j]=1, if(j==1, B[i, 1]=1, B[i, j]=(A^(2*j-1))[i-j+1, 1])); )); A=B); (matrix(#A, #A, r, c, if(r>=c, (A^(2*c))[r-c+1, 1]))^3)[n+3, 3]
CROSSREFS
Cf. A113340, A113350, A113365 (=A113350^3), A113346 (column 0), A113366 (column 1).
Sequence in context: A167713 A219670 A166927 * A228604 A228606 A228605
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Nov 09 2005
STATUS
approved