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A127641
A127640 * A051731 as infinite lower triangular matrices.
3
2, 3, 3, 5, 0, 5, 7, 7, 0, 7, 11, 0, 0, 0, 11, 13, 13, 13, 0, 0, 13, 17, 0, 0, 0, 0, 0, 17, 19, 19, 0, 19, 0, 0, 0, 19, 23, 0, 23, 0, 0, 0, 0, 0, 23, 29, 29, 0, 0, 29, 0, 0, 0, 0, 29, 31, 0, 0, 0, 0, 0, 0, 0, 0, 0, 31, 37, 37, 37, 37, 0, 37, 0, 0, 0, 0, 0, 37, 41, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 41
OFFSET
1,1
COMMENTS
A prime transform of A051731.
EXAMPLE
First few rows of the triangle are:
2;
3, 3;
5, 0, 5;
7, 7, 0, 7;
11, 0, 0, 0, 11;
13, 13, 13, 0, 0, 13;
...
MAPLE
A127640 := proc(n, m) if m < n then 0; else ithprime(n) ; fi ; end: A051731 := proc(n, k) if n mod k = 0 then 1 ; else 0 ; fi ; end: A127641 := proc(n, m) add( A127640(n, k)*A051731(k, m), k=1..n) ; end: for n from 1 to 15 do for m from 1 to n do printf("%d, ", A127641(n, m)) ; od ; od ; # R. J. Mathar, May 19 2007
CROSSREFS
KEYWORD
nonn,tabl,easy
AUTHOR
Gary W. Adamson, Jan 21 2007
EXTENSIONS
More terms from R. J. Mathar, May 19 2007
STATUS
approved