OFFSET
1,2
EXAMPLE
3 divides 12, 5 divides 1215, 7 divides 121520 etc.
MAPLE
A055642 := proc(n) ilog10(n)+ 1; end: Lcat := proc(L) local resul, i ; resul := op(1, L) ; for i from 2 to nops(L) do resul := resul*10^A055642(op(i, L))+op(i, L) ; od ; RETURN(resul) ; end: A091791 := proc(nmax) local a, k, n ; a := [1] ; for n from 2 to nmax do k :=1 ; while Lcat([op(a), k*n]) mod (2*n-1) <> 0 do k := k+1 ; od ; a := [op(a), k*n] ; od; a ; end: A091791(40); # R. J. Mathar, Jul 20 2007
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Feb 18 2004
EXTENSIONS
More terms from R. J. Mathar, Jul 20 2007
STATUS
approved