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A134394 Triangle T(n,k) = Sum_{j=k..n} A077028(j,k), read by rows. 3
1, 2, 1, 3, 3, 1, 4, 6, 4, 1, 5, 10, 9, 5, 1, 6, 15, 16, 12, 6, 1, 7, 21, 25, 22, 15, 7, 1, 8, 28, 36, 35, 28, 18, 8, 1, 9, 36, 49, 51, 45, 34, 21, 9, 1, 10, 45, 64, 70, 66, 55, 40, 24, 10, 1, 11, 55, 81, 92, 91, 81, 65, 46, 27, 11, 1, 12, 66, 100, 117, 120, 112, 96, 75, 52, 30, 12, 1, 13, 78, 121, 145, 153 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Row sums = A055795: (1, 3, 7, 15, 30, 56, 98, ...).

Antidiagonal reading of A139600 without its left column. -_ R. J. Mathar_, Apr 17 2011

LINKS

Table of n, a(n) for n=1..83.

FORMULA

A000012 * A077028 as infinite lower triangular matrices.

T(n,k) = (k-n-1)*( k*(k-n)-2)/2. - R. J. Mathar, Apr 17 2011

EXAMPLE

First few rows of the triangle are:

1;

2, 1;

3, 3, 1;

4, 6, 4, 1;

5, 10, 9, 5, 1;

6, 15, 16, 12, 6, 1;

7, 21, 25, 22, 15, 7, 1;

MAPLE

A077028 := proc(n, k) if n < 0 or k<0 or k > n then 0; else k*(n-k)+1 ; end if; end proc:

A134394 := proc(n, k) add ( A077028(j, k), j=k..n) ; end proc:

seq(seq(A134394(n, k), k=0..n), n=0..15) ; # R. J. Mathar, Apr 17 2011

CROSSREFS

Cf. A077028, A055795.

Sequence in context: A144400 A225281 A057145 * A284855 A074909 A135278

Adjacent sequences:  A134391 A134392 A134393 * A134395 A134396 A134397

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson, Oct 23 2007

STATUS

approved

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Last modified December 16 08:34 EST 2018. Contains 318158 sequences. (Running on oeis4.)