A194991 Primes whose squares are odious.

2, 5, 7, 11, 17, 19, 23, 29, 31, 41, 43, 59, 67, 71, 79, 89, 97, 101, 103, 113, 127, 131, 139, 149, 157, 163, 167, 173, 179, 181, 193, 197, 223, 227, 229, 239, 251, 257, 263, 271, 283, 307, 313, 349, 353, 373, 379, 383, 389, 401, 409, 421, 431, 433, 439, 449, 457, 467, 479, 487, 509, 523, 547, 563

Offset: 1

Author

Vladimir Shevelev, Sep 07 2011

Keywords

• nonn
• base

Comments

Subsequence of the numbers 1, 2, 4, 5, 7, 8, 9, 10, 11, 14, 16, 17, 18, 19, 20, 22, 23, 25, 28, 29, 31, 32, 33, ... which have odious squares. See A235331. - R. J. Mathar, Sep 20 2011

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..5240

Crossrefs

Cf. A000069, A001969, A027697, A027699.

Programs

Magma

[p : p in PrimesInInterval(2, 600) |IsOdd(&+Intseq(p^2, 2))]; // Vincenzo Librandi, Dec 15 2018

Mathematica

Select[Prime@ Range@ 120, OddQ@ First@ DigitCount[#^2, 2] &] (* Amiram Eldar, Dec 14 2018 after Michael De Vlieger at A027697 *)

PARI

isok(p) = isprime(p) && (hammingweight(p^2) % 2); \\ Michel Marcus, Dec 14 2018