OFFSET
1,1
COMMENTS
Elements are squares of integers in (sqrt(91), 10) * sqrt(10)^k without the leading 9 elements for nonnegative k. - David A. Corneth, May 20 2016
LINKS
Nathan Fox, Table of n, a(n) for n = 1..10000
EXAMPLE
61 is a member because 961 = 31^2 is a square.
0 is not a member because 90 is not a square.
MAPLE
t1:=[];
for k from 1 to 50000 do
if issqr(k+9*10^length(k)) then t1:=[op(t1), k]; fi;
od;
t1;
MATHEMATICA
Select[Range[45000], IntegerQ[Sqrt[9*10^IntegerLength[#]+#]]&] (* Harvey P. Dale, Feb 19 2020 *)
PROG
(Magma) [n: n in [1..50000 ] | IsSquare(Seqint(Intseq(n) cat Intseq(9)))]; // Vincenzo Librandi, Feb 20 2020
CROSSREFS
KEYWORD
nonn,base
AUTHOR
STATUS
approved