

A245361


Numbers n such that (reversal of digits of n) + 1 is a square (ignoring leading zeros).


3



3, 8, 30, 36, 42, 51, 53, 80, 84, 99, 300, 323, 341, 360, 384, 387, 420, 422, 426, 510, 530, 552, 575, 576, 591, 800, 825, 827, 840, 861, 882, 990, 993, 998, 3000, 3032, 3069, 3072, 3201, 3230, 3264, 3276, 3410, 3441, 3477, 3483, 3600, 3633, 3648, 3671, 3806
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OFFSET

1,1


COMMENTS

(Reversal of digits of prime p) plus 1 is square is given in A167217.


LINKS



EXAMPLE

84 is in the sequence because reversal of its digits is 48 and 48 + 1 = 49 = 7^2.
510 is in the sequence because reversal of its digits is 15 and 15 + 1 = 16 = 4^2.


MATHEMATICA

Select[Range[10^4], IntegerQ[Sqrt[FromDigits[Reverse[IntegerDigits[#]]] + 1]] &]


PROG

(PARI)
revint(n) = eval(concat(Vecrev(Str(n))))
select(n>issquare(revint(n)+1), vector(4000, n, n)) \\ Colin Barker, Jul 20 2014


CROSSREFS



KEYWORD

nonn,base


AUTHOR



STATUS

approved



