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 A098540 Row sums of triangle A098539, which shifts left one column under the matrix square. 2
 1, 2, 5, 17, 81, 561, 5905, 98673, 2715025, 126550129, 10211715985, 1450856148081, 367849450783633, 168250359224212593, 140078954639877776273, 213886080203739816320113, 602782564524824650717471633 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS PROG (PARI) a(n)=local(A, B, C, m); A=matrix(1, 1); A[1, 1]=1; for(m=2, n+1, B=A^2; C=matrix(m, m); for(j=1, m, for(k=1, j, if(j<3 || k==j || k>m-1, C[j, k]=1, if(k==1, C[j, k]=B[j-1, 1], C[j, k]=B[j-1, k-1])); )); A=C); sum(i=1, n+1, A[n+1, i]) CROSSREFS Cf. A098539, A098541. Sequence in context: A125282 A020125 A076322 * A079574 A032262 A144259 Adjacent sequences:  A098537 A098538 A098539 * A098541 A098542 A098543 KEYWORD nonn AUTHOR Paul D. Hanna, Sep 13 2004 STATUS approved

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Last modified January 25 23:08 EST 2020. Contains 331270 sequences. (Running on oeis4.)