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%I #15 May 24 2017 21:06:36
%S 3,8,30,36,42,51,53,80,84,99,300,323,341,360,384,387,420,422,426,510,
%T 530,552,575,576,591,800,825,827,840,861,882,990,993,998,3000,3032,
%U 3069,3072,3201,3230,3264,3276,3410,3441,3477,3483,3600,3633,3648,3671,3806
%N Numbers n such that (reversal of digits of n) + 1 is a square (ignoring leading zeros).
%C (Reversal of digits of prime p) plus 1 is square is given in A167217.
%H K. D. Bajpai, <a href="/A245361/b245361.txt">Table of n, a(n) for n = 1..6696</a>
%e 84 is in the sequence because reversal of its digits is 48 and 48 + 1 = 49 = 7^2.
%e 510 is in the sequence because reversal of its digits is 15 and 15 + 1 = 16 = 4^2.
%t Select[Range[10^4],IntegerQ[Sqrt[FromDigits[Reverse[IntegerDigits[#]]] + 1]] &]
%o (PARI)
%o revint(n) = eval(concat(Vecrev(Str(n))))
%o select(n->issquare(revint(n)+1), vector(4000, n, n)) \\ _Colin Barker_, Jul 20 2014
%Y Cf. A000290, A061230, A061457, A167217.
%K nonn,base
%O 1,1
%A _K. D. Bajpai_, Jul 18 2014
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