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A105622 Row sums of triangle A105620. 1
1, 0, -3, -16, -104, -908, -9980, -130756, -1978044, -33864628, -646882700, -13637768276, -314550050684, -7879500818548, -213050486593260, -6184793428783156, -191870459680722524, -6335136849263878868, -221817478808912340620, -8209644712019737332436 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

A105620 is the matrix inverse square-root of triangle A105615.

LINKS

Table of n, a(n) for n=0..19.

PROG

(PARI) {a(n)=local(R, M=matrix(n+3, n+3, 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)))))); R=(M+M^0)/2; for(i=1, floor(2*log(n+2)), R=(R+M*R^(-1))/2); return(if(n<0, 0, sum(k=0, n, R[n+1, k+1])))}

CROSSREFS

Cf. A105615, A105620.

Sequence in context: A207434 A074542 A344216 * A110903 A206351 A085614

Adjacent sequences:  A105619 A105620 A105621 * A105623 A105624 A105625

KEYWORD

sign

AUTHOR

Paul D. Hanna, Apr 16 2005

STATUS

approved

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Last modified May 28 05:47 EDT 2022. Contains 354112 sequences. (Running on oeis4.)