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A143956 Triangle read by rows, A000012 * A136521 * A000012; 1<=k<=n. 0
1, 3, 2, 5, 4, 2, 7, 6, 4, 2, 9, 8, 6, 4, 2, 11, 10, 8, 6, 4, 2, 13, 12, 10, 8, 6, 4, 2, 15, 14, 12, 10, 8, 6, 4, 2, 17, 16, 14, 12, 10, 8, 6, 4, 2, 19, 18, 16, 14, 12, 10, 8, 6, 4, 2, 21, 20, 18, 16, 14, 12, 10, 8, 6, 4, 2 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Row sums = A028387: (1, 5, 11, 19, 29, 41,...)

LINKS

Table of n, a(n) for n=1..66.

FORMULA

Triangle read by rows, A000012 * A136521 * A000012; 1<=k<=n. A136521 = an infinite lower triangular matrix with (1,2,2,2,...) in the main diagonal the rest zeros.

EXAMPLE

First few rows of the triangle =

1;

3, 2;

5, 4, 2;

7, 6, 4, 2;

9, 8, 6, 4, 2;

11, 10, 8, 6, 4, 2;

13, 12, 10, 8, 6, 4, 2;

15, 14, 12, 10, 8, 6, 4, 2;

...

CROSSREFS

Cf. A136521, A028387.

Sequence in context: A130912 A178844 A210714 * A110661 A143124 A205400

Adjacent sequences:  A143953 A143954 A143955 * A143957 A143958 A143959

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson & Roger L. Bagula, Aug 26 2008

STATUS

approved

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Last modified May 29 09:00 EDT 2020. Contains 334697 sequences. (Running on oeis4.)