OFFSET
1,1
COMMENTS
From Robert Israel, Jun 06 2018: (Start)
Numbers k such that 10^m+1 | (k+1)^2-2 where (k+1)^2 has 2*m digits.
Includes 10^i - 10^(3*i) + 10^(4*i) for all i >= 1. (End)
LINKS
Robert Israel, Table of n, a(n) for n = 1..600
EXAMPLE
99000100 * 99000102 = 98010199//98010200, where // denotes concatenation.
MAPLE
Res:= NULL:
for d from 1 to 40 do
Res:= Res, op(sort(select(t -> t^2 >= 10^(2*d-1), map(t -> rhs(op(t))-1, [msolve(x^2=2, 10^d+1)]))))
od:
Res; # Robert Israel, Jun 06 2018
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Giovanni Resta, Feb 06 2006
STATUS
approved