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A113380
Column 1 of triangle A113378, also equals column 0 of A113389^4.
2
1, 12, 168, 3190, 80136, 2553162, 99579994, 4624245724, 250138459808, 15488221792442, 1082305443525010, 84364431201000877, 7264439969560330768, 685338322012632405151, 70341947440289270101707
OFFSET
0,2
FORMULA
A113378 equals the matrix cube of A113370, which has the property: column k of A113370^3 = column 0 of A113389^(3*k+1) for k>=0.
PROG
(PARI) a(n)=local(A, B); A=Mat(1); for(m=2, n+2, 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^(3*j-2))[i-j+1, 1])); )); A=B); (A^3)[n+2, 2]
CROSSREFS
Cf. A113378, A113370, A113389, A113379 (column 0).
Sequence in context: A320761 A282045 A304960 * A071103 A012489 A027772
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Nov 14 2005
STATUS
approved