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A104448 Row sums of triangle A104446. 1
1, 3, 6, 13, 33, 101, 372, 1624, 8263, 48285, 320031, 2380114, 19675986, 179314868, 1788473424, 19398149629, 227510745445, 2871040422932, 38810001746171, 559745948482030, 8582882169611759, 139467832061599433 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

A104446 equals the square of triangular matrix A104445, read by rows, where X=[A104445] satisfies: SHIFT_LEFT_UP(X) = X^2 - X + I.

LINKS

Table of n, a(n) for n=0..21.

FORMULA

a(n) = A091352(n) + A091352(n-1) for n>0.

PROG

(PARI) a(n)=local(A=Mat(1), B); for(m=1, n+1, B=A^2-A+A^0; A=matrix(m+1, m+1); for(i=1, m+1, for(j=1, i, if(i<2 || j==i, A[i, j]=1, if(j==1, A[i, j]=1, A[i, j]=B[i-1, j-1]))))); return(sum(k=1, n+1, (A^2)[n+1, k]))

CROSSREFS

Cf. A104446, A104445, A091352, A091351.

Sequence in context: A179928 A026538 A201951 * A062466 A053564 A264236

Adjacent sequences:  A104445 A104446 A104447 * A104449 A104450 A104451

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Mar 08 2005

STATUS

approved

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Last modified October 1 08:39 EDT 2020. Contains 337442 sequences. (Running on oeis4.)