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A143102 Triangle read by rows, A000012 * (A143097 * 0^(n-k)) * A000012, 1<=k<=n. 1
1, 2, 3, 4, 6, 7, 3, 7, 9, 10, 5, 8, 12, 14, 15, 7, 12, 15, 29, 21, 22, 6, 18, 18, 21, 25, 27, 28, 8, 14, 21, 26, 29, 33, 35, 36, 10, 18, 24, 31, 36, 39, 43, 45, 46, 9, 19, 27, 33, 40, 45, 48, 52, 54, 55, 11, 20, 30, 38, 44, 51, 56, 59, 63, 65, 66, 13, 24, 33, 43, 51, 57, 64, 69, 72 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Left border = A143097: (1, 2, 4, 3, 5, 7, 6, 8,...); right border = A143101, partial sums of A143097: (1, 3, 7, 10, 15, 22, 28,...).

Row sums = A143103: (1, 5, 17, 29, 54, 96,...).

LINKS

Table of n, a(n) for n=1..75.

FORMULA

Triangle read by rows, A000012 * (A143097 * 0(n-k)) * A000012, 1<=k<=n; where = A000012 = an infinite lower triangular matrix with all 1's and A143097 * 0^(n-k) = an infinite lower triangular matrix with A143097 (1, 2, 4, 3, 5, 7, 6,...) in the main diagonal and the rest zeros.

EXAMPLE

First few rows of the triangle are:

1;

2, 3;

4, 6, 7;

3, 7, 9, 10;

5, 8, 12, 14, 15;

7, 12, 15, 19, 21, 22;

6, 13, 18, 21, 25, 27, 28;

...

CROSSREFS

Cf. A143097, A143101, A143103.

Sequence in context: A030209 A265399 A138588 * A013944 A123497 A123501

Adjacent sequences:  A143099 A143100 A143101 * A143103 A143104 A143105

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson, Jul 24 2008

STATUS

approved

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Last modified June 17 06:06 EDT 2019. Contains 324183 sequences. (Running on oeis4.)