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A121306
Array read by antidiagonals: a(m,n) = a(m,n-1)+a(m-1,n) but with initialization values a(0,0)=0, a(m>=1,0)=1, a(0,1)=1, a(0,n>1)=0.
4
2, 2, 3, 2, 5, 4, 2, 7, 9, 5, 2, 9, 16, 14, 6, 2, 11, 25, 30, 20, 7, 2, 13, 36, 55, 50, 27, 8, 2, 15, 49, 91, 105, 77, 35, 9, 2, 17, 64, 140, 196, 182, 112, 44, 10, 19, 81, 204, 336, 378, 294, 156, 54, 100, 285, 540, 714, 672, 450, 210, 385, 825, 1254, 1386, 1122
OFFSET
0,1
COMMENTS
For a(1,0)=1, a(m>1,0)=0 and a(0,n>=0)=0 one gets Pascal's triangle A007318.
FORMULA
a(m,n) = a(m,n-1)+a(m-1,n), a(0,0)=0, a(m>=1,0)=1, a(0,1)=1, a(0,n>1)=0.
EXAMPLE
Array begins
2 2 2 2 2 2 2 2 2 ...
3 5 7 9 11 13 15 17 19 ...
4 9 16 25 36 49 64 81 100 ...
5 14 30 55 91 140 204 285 385 ...
6 20 50 105 196 336 540 825 1210 ...
7 27 77 182 378 714 1254 2079 3289 ...
PROG
(Excel) =Z(-1)S+ZS(-1). The very first row (not included into the table) contains the initialization values: a(0, 1)=1, a(0, n>=2)=0. The very first column (not included into the table) contains the initialization values: a(m>=1, 0)=1. The value a(0, 0)=0 does not enter into the table.
KEYWORD
nonn,tabl
AUTHOR
Thomas Wieder, Aug 04 2006, Aug 06 2006
EXTENSIONS
Edited by N. J. A. Sloane, Sep 15 2006
STATUS
approved