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A106209 Row sums of triangle A106208. 1
1, 2, 6, 30, 231, 2453, 33393, 556999, 11039026, 254128870, 6677972615, 197547561340, 6504619941881, 236165840696980, 9380353293627619, 404848232250564042, 18875601922237847288, 945875935431064488637 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..17.

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]=j, if(j==1, B[i, j]=(A^2)[i-1, 1], B[i, j]=(A^2)[i-1, j])); )); A=B); return(sum(k=0, n, A[n+1, k+1]/(k+1)))}

CROSSREFS

Cf. A106208.

Sequence in context: A089459 A027882 A306782 * A003266 A303169 A097385

Adjacent sequences:  A106206 A106207 A106208 * A106210 A106211 A106212

KEYWORD

nonn

AUTHOR

Paul D. Hanna, May 01 2005

STATUS

approved

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Last modified April 15 20:25 EDT 2021. Contains 342977 sequences. (Running on oeis4.)