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A376235
Prime numbers with Hamming weight neither prime nor a power of 2.
0
311, 317, 347, 349, 359, 373, 461, 467, 571, 599, 619, 683, 691, 739, 797, 811, 821, 839, 853, 857, 881, 907, 937, 977, 991, 1019, 1021, 1103, 1117, 1181, 1223, 1229, 1237, 1279, 1303, 1307, 1319, 1381, 1427, 1429, 1433, 1471, 1481, 1489, 1531, 1559, 1579, 1607, 1613, 1619, 1621, 1637, 1663
OFFSET
1,1
COMMENTS
Surprisingly, all primes less than 311 have a Hamming weight (sum of their binary digits: A000120) equal to either a prime or a power of two (cf. A174090). But for larger primes, exceptions become more and more frequent.
PROG
(PARI) select( {is_A376235(n)=!is_A174090(hammingweight(n))&&isprime(n)}, [0..2222])
CROSSREFS
Cf. A000120 (binary or Hamming weight), A174090 (union of primes and powers of two).
Sequence in context: A281568 A084876 A190567 * A060339 A046016 A142005
KEYWORD
nonn
AUTHOR
M. F. Hasler, Oct 24 2024
STATUS
approved