A070254 Perfect squares one more than a palindrome.

1, 4, 9, 100, 324, 576, 4225, 5776, 10000, 36864, 42025, 1000000, 3055504, 3640464, 5597956, 8803089, 32855824, 100000000, 360696064, 422919225, 10000000000, 30485858404, 30536863504, 32154945124, 59080108096, 86310801369, 304816618404, 1000000000000, 3490500050944

Offset: 1

Author

Amarnath Murthy, May 06 2002

Keywords

• nonn
• base

Comments

All even powers of 10 are members of both A070254 and A027720.

Links

• Giovanni Resta, Table of n, a(n) for n = 1..53

Crossrefs

Cf. A028504, A027719, A027720, A070253.

Programs

Mathematica

Do[ If[a = IntegerDigits[n^2 - 1]; a == Reverse[a], Print[n^2]], {n, 1, 10^6}]
Select[Range[300000]^2,PalindromeQ[#-1]&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Aug 06 2018 *)

Formula

a(n) = A070253(n)^2 = A028504(n) + 1. - Giovanni Resta, Aug 29 2018

Extensions

Edited by Jason Earls and Robert G. Wilson v, May 08 2002

Offset changed by and more terms from Giovanni Resta, Aug 28 2018