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 A105631 Row sums of triangle A105629, which is the matrix logarithm of triangle A105623. 1
 0, 1, 5, 27, 195, 1833, 21125, 286451, 4453859, 78031153, 1520668645, 32631020011, 764640901539, 19431070911513, 532315915981605, 15640217893829891, 490640673319698179, 16368499360721508833, 578693283962999831365 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS A105623 equals the matrix square-root of triangle A105615. LINKS PROG (PARI) {a(n)=local(L, M=matrix(n+1, n+1, m, j, if(m>=j, if(m==j, 1, if(m==j+1, -2*j, polcoeff(1/sum(i=0, m-j, (2*i)!/i!/2^i*x^i)+O(x^m), m-j)))))^-1); L=sum(i=1, #M, (-1)^(i-1)*(M-M^0)^i/i); return(if(n<0, 0, sum(k=0, n, L[n+1, k+1])/2))} CROSSREFS Cf. A105629, A105623, A105615. Sequence in context: A240637 A023811 A126119 * A167019 A230563 A204266 Adjacent sequences:  A105628 A105629 A105630 * A105632 A105633 A105634 KEYWORD nonn AUTHOR Paul D. Hanna, Apr 16 2005 STATUS approved

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Last modified October 26 08:06 EDT 2020. Contains 338027 sequences. (Running on oeis4.)