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A111977 Row sums of triangle A111975, which shifts columns left and up under matrix square. 1
1, 2, 4, 13, 57, 369, 3681, 59073, 1579393, 72188673, 5749089793, 809616264193, 204018868459521, 92907742733348865, 77097057406948106241, 117413997231333438701569, 330195264668839727287861249 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..16.

PROG

(PARI) {a(n, q=2)=local(A=Mat(1), B); if(n<0, 0, for(m=1, n+2, B=matrix(m, m); for(i=1, m, for(j=1, i, if(j==i, B[i, j]=1, if(j==1, B[i, j]=if(i>2, (A^q)[i-1, 2], 1), B[i, j]=(A^q)[i-1, j-1])); )); A=B); return(sum(k=0, n, A[n+1, k+1])))}

CROSSREFS

Cf. A111975 (triangle), A078537 (variant).

Sequence in context: A328438 A039831 A173184 * A201691 A020120 A020097

Adjacent sequences:  A111974 A111975 A111976 * A111978 A111979 A111980

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Aug 25 2005

STATUS

approved

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Last modified January 26 14:08 EST 2020. Contains 331280 sequences. (Running on oeis4.)