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A131819
A131818 * A000012 as infinite lower triangular matrices. Triangle read by rows, partial sums starting from the right of A131818.
1
1, 4, 2, 8, 5, 3, 13, 9, 7, 4, 19, 14, 12, 9, 5, 26, 20, 18, 15, 11, 6, 34, 27, 25, 22, 18, 13, 7, 43, 35, 33, 30, 26, 21, 15, 8, 53, 44, 42, 39, 35, 30, 24, 17, 9, 64, 54, 52, 49, 45, 40, 34, 27, 19, 10, 76, 65, 63, 60, 56, 51, 45, 38, 30, 21, 11
OFFSET
1,2
COMMENTS
Left column = A034856: (1, 4, 8, 13, 19, 26, 34, ...). Row sums = A131820: (1, 6, 16, 33, 59, 96, ...).
EXAMPLE
First few rows of the triangle:
1;
4, 2;
8, 5, 3;
13, 9, 7, 4;
19, 14, 12, 9, 5;
26, 20, 18, 15, 11, 6;
34, 27, 25, 22, 18, 13, 7;
...
PROG
(PARI) tabl(nn) = {m131818 = matrix(nn, nn, n, k, if (k==1, n, if (k <= n, k, 0))); m000012 = matrix(nn, nn, n, k, (k<=n)); m131819 = m131818 * m000012; for (n = 1, nn, for (k = 1, n, print1(m131819[n, k], ", "); ); ); } \\ Michel Marcus, Feb 12 2014
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson, Jul 18 2007
EXTENSIONS
More terms from Michel Marcus, Feb 12 2014
STATUS
approved