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A267117 Numbers n such that in their prime factorization n = p_1^e_1 * ... * p_k^e_k, there is no digit-position in the base-2 representation of the exponents e_1 .. e_k such that in that position all those exponents would have 1-bit. 5
1, 12, 18, 20, 28, 44, 45, 48, 50, 52, 60, 63, 68, 75, 76, 80, 84, 90, 92, 98, 99, 112, 116, 117, 124, 126, 132, 140, 144, 147, 148, 150, 153, 156, 162, 164, 171, 172, 175, 176, 180, 188, 192, 198, 204, 207, 208, 212, 220, 228, 234, 236, 240, 242, 244, 245, 252, 260, 261, 268, 272, 275, 276, 279, 284, 288, 292, 294, 300 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..10000

EXAMPLE

60 = 2^2 * 3^1 * 5^1 is included, as bitwise-anding together the binary representations of the exponents, "10", "01" and "01" results "00", zero.

MATHEMATICA

{1}~Join~Select[Range@ 300, BitAnd @@ Map[Last, FactorInteger@ #] == 0 &] (* Michael De Vlieger, Feb 07 2016 *)

PROG

(Scheme, with Antti Karttunen's IntSeq-library)

(define A267117 (ZERO-POS 1 1 A267115))

CROSSREFS

Indices of zeros in A267115.

Cf. A054753 (subsequence), A191555 (subsequence after the initial 2).

Cf. also A267114, A268376.

Sequence in context: A070011 A084679 A072588 * A187039 A325241 A072357

Adjacent sequences:  A267114 A267115 A267116 * A267118 A267119 A267120

KEYWORD

nonn,base

AUTHOR

Antti Karttunen, Feb 03 2016

EXTENSIONS

Erroneous claim corrected by Antti Karttunen, Feb 07 2016

STATUS

approved

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Last modified July 12 09:35 EDT 2020. Contains 335657 sequences. (Running on oeis4.)