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A102229
Column 1 of triangular matrix A102228, in which the first differences of row k forms row (k+1) of its matrix square-root (A102225).
3
0, 1, -2, -13, -34, -214, -1080, -17748, -210687, -12958931, -336158195, -90749332418, -5514826306078, -6602085964032676, -1100107197850536319, -5281354412162659396395, -2833757368893623973093411, -48664369321649964841252244730
OFFSET
0,3
PROG
(PARI) {a(n)=local(A=matrix(2, 2), B); A[1, 1]=1; for(m=2, n+1, 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]=(A^2)[i-1, 1], B[i, j]=(A^2)[i-1, j]-(A^2)[i-1, j-1])); )); A=B); return((A^2)[n+1, 2])}
CROSSREFS
KEYWORD
sign
AUTHOR
Paul D. Hanna, Jan 01 2005
STATUS
approved