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A074883
Triangle generated by Pascal's rule, except begin and end the n-th row with sigma(n).
0
1, 3, 3, 4, 6, 4, 7, 10, 10, 7, 6, 17, 20, 17, 6, 12, 23, 37, 37, 23, 12, 8, 35, 60, 74, 60, 35, 8, 15, 43, 95, 134, 134, 95, 43, 15, 13, 58, 138, 229, 268, 229, 138, 58, 13, 18, 71, 196, 367, 497, 497, 367, 196, 71, 18
OFFSET
1,2
EXAMPLE
Triangle begins:
1;
3, 3;
4, 6, 4;
7, 10, 10, 7;
6, 17, 20, 17, 6;
12, 23, 37, 37, 23, 12;
8, 35, 60, 74, 60, 35, 8;
PROG
(PARI) t(n, k) = {if (k<1 || k>n, return (0)); if (k==1 || k==n, return (sigma(n))); return (t(n-1, k-1) + t(n-1, k)); }
tabl(nn) = {for (n=1, nn, for (k=1, n, print1(t(n, k), ", "); ); print(); ); } \\ Michel Marcus, May 19 2013
CROSSREFS
Sequence in context: A196485 A196718 A265652 * A338015 A196245 A337019
KEYWORD
easy,nonn,tabl
AUTHOR
Joseph L. Pe, Sep 30 2002
EXTENSIONS
More terms from Michel Marcus, May 19 2013
STATUS
approved