OFFSET
1,3
COMMENTS
The sequence is infinite since if k is a term then so is 1k1.
LINKS
Michael S. Branicky, Table of n, a(n) for n = 1..10000
EXAMPLE
k(6) = 19 becomes 181 as 1^2 = 1 and 9^2 = 81;
k(7) = 22 becomes 44 as 2^2 = 4 and 2^2 = 4;
k(8) = 28 becomes 464 as 2^2 = 4 and 8^2 = 64; etc.
MATHEMATICA
Select[Range[0, 3000], PalindromeQ@FromDigits@Flatten[IntegerDigits/@(IntegerDigits@#^2)]&]
PROG
(Python)
def ok(n): return (s:="".join(str(int(d)**2) for d in str(n))) == s[::-1]
print([k for k in range(3000) if ok(k)]) # Michael S. Branicky, Oct 05 2023
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Eric Angelini and Giorgos Kalogeropoulos, Oct 05 2023
STATUS
approved