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A234037 The union of odious numbers with evil squares and evil numbers with odious squares. 1
5, 9, 10, 13, 17, 18, 20, 21, 23, 26, 29, 33, 34, 36, 37, 39, 40, 42, 43, 46, 47, 51, 52, 58, 61, 65, 66, 68, 69, 71, 72, 73, 74, 75, 77, 78, 80, 81, 84, 85, 86, 89, 92, 93, 94, 95, 101, 102, 104, 107, 109, 113, 115, 116, 122, 125, 129, 130, 132, 133, 135, 136, 137 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Numbers n with odd sum of binary weight of n and binary weight of n^2.

Primes are in this sequence: 5, 13, 17, 23, 29, 37, 43, 47, 61, 71, 73,....

Evil numbers with odious squares: 5, 9, 10, 17, 18, 20, 23, 29, 33, 34,...

Odious numbers with evil squares: 13, 21, 26, 37, 42, 47, 52, 61, 69,...

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

EXAMPLE

a(3) = 10 because 2 (binary weight of 10) + 3 (binary weight of 100) = 5 (odd).

a(4) = 13 because 3 (binary weight of 13) + 4 (binary weight of 169) = 7 (odd).

MATHEMATICA

Select[Range[100], Mod[DigitCount[#, 2, 1], 2] != Mod[DigitCount[#^2, 2, 1], 2] &] (* Amiram Eldar, Aug 31 2020 *)

CROSSREFS

Cf. A000069, A000120, A001969, A159918, A231431, A235001.

Sequence in context: A135980 A314579 A070873 * A225836 A140509 A314580

Adjacent sequences: A234034 A234035 A234036 * A234038 A234039 A234040

KEYWORD

nonn,base

AUTHOR

Gerasimov Sergey, Jan 13 2014

EXTENSIONS

Wrong term removed by Amiram Eldar, Aug 31 2020

STATUS

approved

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Last modified February 5 03:48 EST 2023. Contains 360082 sequences. (Running on oeis4.)