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A194991 Primes whose squares are odious. 3
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

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

MATHEMATICA

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

PROG

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

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

CROSSREFS

Cf. A000069, A001969, A027697, A027699.

Sequence in context: A144832 A309290 A023238 * A319596 A235480 A049042

Adjacent sequences:  A194988 A194989 A194990 * A194992 A194993 A194994

KEYWORD

nonn,base

AUTHOR

Vladimir Shevelev, Sep 07 2011

STATUS

approved

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Last modified May 12 13:46 EDT 2021. Contains 343823 sequences. (Running on oeis4.)