A074883 - OEIS

A074883

Triangle generated by Pascal's rule, except begin and end the n-th row with sigma(n).

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

(list; table; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

Table of n, a(n) for n=1..55.

EXAMPLE

Triangle begins:

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

Adjacent sequences: A074880 A074881 A074882 * A074884 A074885 A074886

KEYWORD

easy,nonn,tabl

AUTHOR

Joseph L. Pe, Sep 30 2002

EXTENSIONS

More terms from Michel Marcus, May 19 2013

STATUS

approved