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 A102226 Column 0 of triangular matrix A102225, in which row k is formed from the first differences of row (k-1) of its matrix square (A102228). 4
 1, 1, 2, 3, 7, 17, 75, 346, 4874, 49047, 3009094, 69540959, 19266759978, 1145861630146, 1316021940482105, 231957006949639674, 1000756528918141445755, 578298169571294295021140 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Also equals column 0 of A102228 shift one place right. LINKS FORMULA a(n) = A102229(n-1) - A102227(n) for n>=2, where A102227 equals column 1 of A102225 and A102229 equals column 1 of A102228. PROG (PARI) {a(n)=local(A=matrix(1, 1), 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[n+1, 1])} CROSSREFS Cf. A102225, A102227, A102228, A102229. Sequence in context: A281368 A330726 A059801 * A195530 A295509 A225747 Adjacent sequences:  A102223 A102224 A102225 * A102227 A102228 A102229 KEYWORD nonn AUTHOR Paul D. Hanna, Jan 01 2005 STATUS approved

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Last modified February 26 08:33 EST 2020. Contains 332277 sequences. (Running on oeis4.)