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A167737
Primes that becomes a square when prefixed with a 4.
8
41, 761, 23801, 31649, 39569, 63761, 1100921, 1951529, 2497361, 2810849, 3046721, 3678881, 4715969, 4796249, 5118089, 5198729, 5441081, 5846441, 5927729, 6009089, 6498761, 6662561, 6908801, 7238129, 7983329, 8149721, 8483369, 8734361, 9744809, 9829481
OFFSET
1,1
LINKS
MAPLE
map(t -> t - 4*10^ilog10(t), select(t -> isprime(t - 4*10^ilog10(t)), [seq(seq(i^2, i=ceil(sqrt(4.1*10^d)) .. floor(sqrt(5*10^d))), d=1..10)])); # Robert Israel, Nov 08 2023
MATHEMATICA
Select[Prime[Range[10^4]], IntegerQ[Sqrt[FromDigits[Join[{4}, IntegerDigits[#]]]]]&] (* G. C. Greubel, Jun 23 2016 *)
KEYWORD
base,nonn
AUTHOR
Claudio Meller, Nov 10 2009
EXTENSIONS
More terms from Michel Marcus, Aug 05 2013
STATUS
approved