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A267490 Primes whose base-8 representation is a perfect square in base 10.

%I A267490 #27 Sep 08 2022 08:46:15
%S A267490 149,241,661,1409,2593,3733,6257,7793,15313,23189,25601,26113,30497,
%T A267490 34337,44053,49057,78577,92821,95009,108529,115861,132757,162257,
%U A267490 178417,183377,223381,235541,242197,266261,327317,345749,426389,525461,693397,719893,729713,805397,814081,903841
%N A267490 Primes whose base-8 representation is a perfect square in base 10.
%C A267490 Subsequence of primes in A267768. - _M. F. Hasler_, Jan 20 2016
%H A267490 Chai Wah Wu, <a href="/A267490/b267490.txt">Table of n, a(n) for n = 1..10000</a>
%e A267490 a(1) = 149 because 149 is 225 in base 8, and 225 is 15^2 in base 10.
%t A267490 Select[Prime@ Range[10^5], IntegerQ@ Sqrt@ FromDigits@ IntegerDigits[#, 8] &] (* _Michael De Vlieger_, Jan 16 2016 *)
%o A267490 (PARI) listp(nn) = {forprime(p=1, nn, d = digits(p, 8); pd = Pol(d); if (issquare(subst(pd, x, 10)), print1(p, ", ")););} \\ _Michel Marcus_, Jan 16 2016
%o A267490 (PARI) is(n,b=8,c=10)={issquare(subst(Pol(digits(n,b)),x,c))&&isprime(n)} \\ _M. F. Hasler_, Jan 20 2016
%o A267490 (Python)
%o A267490 from sympy import isprime
%o A267490 A267490_list = [int(s,8) for s in (str(i**2) for i in range(10**6)) if max(s) < '8' and isprime(int(s,8))] # _Chai Wah Wu_, Jan 20 2016
%o A267490 (Magma) [n:n in PrimesUpTo(1000000)| IsSquare(Seqint(Intseq(n,8)))]; // _Marius A. Burtea_, Jun 30 2019
%Y A267490 For primes which are primes in other bases, see A235265, A235266, A152079, A235461 - A235482, A065720 ⊂ A036952, A065721 - A065727, A235394, A235395, A089971 ⊂ A020449, A089981, A090707 - A091924.
%K A267490 nonn,base
%O A267490 1,1
%A A267490 _Christopher Cormier_, Jan 16 2016