OFFSET
1,2
COMMENTS
The squares are in A225885.
The first three terms have a single-digit square which by convention yields 0 if the first digit is removed. The first 6 terms are the only terms of the sequence not divisible by 5.
LINKS
Chai Wah Wu, Table of n, a(n) for n = 1..5000
MATHEMATICA
b /. Flatten[Outer[Solve[a^2 + #2*10^#1 == b^2 && 0 <= a < Sqrt[10^#1] && Sqrt[#2*10^#1] <= b < Sqrt[10^(#1 + 1)], {a, b}, Integers] &, Range[0, 5], Range[9]], 2] (* Davin Park, Dec 30 2016 *)
Sqrt[#]&/@Select[Range[2500]^2, IntegerQ[Sqrt[FromDigits[ Rest[ IntegerDigits[ #]]]]]&] (* Harvey P. Dale, May 01 2017 *)
PROG
(PARI) is(n)=issquare(n^2%10^(#Str(n^2)-1))
CROSSREFS
KEYWORD
nonn,base
AUTHOR
M. F. Hasler, Nov 01 2014
STATUS
approved