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A072367 Squares x such that x + reverse of x is a prime. 2
1, 100, 196, 625, 10816, 13456, 15376, 18496, 21025, 22201, 22801, 24649, 25921, 27889, 29929, 33856, 35344, 36100, 42025, 50176, 60025, 63001, 70756, 71824, 73984, 78400, 82369, 83521, 96100, 1012036, 1048576, 1073296, 1123600, 1144900 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

EXAMPLE

196 is a term because 196 is a square and 196+691=887 is a prime.

MAPLE

select(t -> isprime(t+revdigs(t)), [seq(i^2, i=1..10000)]); # Robert Israel, Jun 19 2019

MATHEMATICA

Select[Range[1100]^2, PrimeQ[#+FromDigits[Reverse[IntegerDigits[#]]]]&]  (* Harvey P. Dale, Feb 20 2011 *)

PROG

(PARI) isok(x) = issquare(x) && isprime(x+fromdigits(Vecrev(digits(x)))); \\ Michel Marcus, Jun 19 2019

(MAGMA) [k:k in [m^2:m in [1..1100]]| IsPrime(Seqint(Intseq(k, 10))+Seqint(Reverse(Intseq(k, 10))))]; // Marius A. Burtea, Jun 20 2019

CROSSREFS

Cf. A056964, A072366.

Sequence in context: A068805 A231088 A104023 * A172178 A036742 A262198

Adjacent sequences:  A072364 A072365 A072366 * A072368 A072369 A072370

KEYWORD

base,easy,nonn

AUTHOR

Shyam Sunder Gupta, Jul 18 2002

STATUS

approved

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Last modified August 3 18:51 EDT 2020. Contains 336201 sequences. (Running on oeis4.)