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A268376 Numbers n for which A001222(n) > A267116(n). 6
6, 10, 14, 15, 21, 22, 24, 26, 30, 33, 34, 35, 36, 38, 39, 40, 42, 46, 51, 54, 55, 56, 57, 58, 60, 62, 65, 66, 69, 70, 72, 74, 77, 78, 82, 84, 85, 86, 87, 88, 90, 91, 93, 94, 95, 96, 100, 102, 104, 105, 106, 108, 110, 111, 114, 115, 118, 119, 120, 122, 123, 126, 129, 130, 132, 133, 134, 135, 136, 138, 140, 141 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Numbers n such that in their prime factorization n = p_1^e_1 * ... * p_k^e_k, there is at least one pair of exponents e_i and e_j (i and j distinct), such that their base-2 representations have at least one shared digit-position in which both exponents have 1-bit.

LINKS

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

EXAMPLE

n = 6 = 2^1 * 3^1 is included as both exponents, 1 and 1 ("1" in binary) have both 1-bit in position 0 of their binary representations.

n = 24 = 2^3 * 3^1 is included as both exponents, 1 and 3 ("01" and "11" in binary) have both 1-bit in position 0 of their binary representations.

n = 36 = 2^2 * 3^2 is included as both exponents, 2 and 2 ("10" in binary) have both 1-bit in position 1 of their binary representations.

n = 60 = 2^2 * 3^1 * 5^1 is included as the exponents of 3 and 5, both of which are 1, have both 1-bit in position 1 of their binary representations.

MATHEMATICA

Select[Range@ 144, PrimeOmega@ # > BitOr @@ Map[Last, FactorInteger@ #] &] (* Michael De Vlieger, Feb 04 2016 *)

PROG

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

(define A268376 (NONZERO-POS 1 1 A268374))

CROSSREFS

Cf. A001222, A267116.

Indices of nonzeros in A268374.

Subsequence of A002808 and A024619.

Cf. A268375 (complement).

Cf. A260730 (subsequence).

Cf. also A267117.

Differs from A067582(n+1) for the first time at n=25, where a(n) = 60, a value which is missing from A067582.

Sequence in context: A063763 A115956 A066073 * A067582 A229153 A119847

Adjacent sequences:  A268373 A268374 A268375 * A268377 A268378 A268379

KEYWORD

nonn,base

AUTHOR

Antti Karttunen, Feb 03 2016

STATUS

approved

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Last modified October 13 23:52 EDT 2019. Contains 327983 sequences. (Running on oeis4.)