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A113356
Column 0 of triangle A113355, which is the matrix square of A113350.
4
1, 4, 18, 112, 965, 10957, 156699, 2727793, 56306695, 1350043964, 36979531548, 1141573025171, 39272377323692, 1491452150268435, 62027842189908230, 2805631215820328991, 137199563717151509076, 7215932308408758314446
OFFSET
0,2
FORMULA
a(n) = A113346(n+1) - 1, where A113346 equals column 0 of triangle A113345 (=A113340^2).
PROG
(PARI) a(n)=local(A, B); A=matrix(1, 1); A[1, 1]=1; for(m=2, n+1, 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]))^2)[n+1, 1]
CROSSREFS
Cf. A113340, A113350, A113355, A113357 (column 1), A113358 (column 2), A113359 (column 3).
Sequence in context: A364623 A143920 A233534 * A062805 A326093 A222584
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Nov 08 2005
STATUS
approved