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A336101 Numbers divisible by exactly one odd prime. 7
3, 5, 6, 7, 9, 10, 11, 12, 13, 14, 17, 18, 19, 20, 22, 23, 24, 25, 26, 27, 28, 29, 31, 34, 36, 37, 38, 40, 41, 43, 44, 46, 47, 48, 49, 50, 52, 53, 54, 56, 58, 59, 61, 62, 67, 68, 71, 72, 73, 74, 76, 79, 80, 81, 82, 83, 86, 88, 89, 92, 94, 96, 97, 98, 100, 101, 103, 104 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Numbers k for which A001221(A000265(k)) = 1. - Antti Karttunen, Jul 08 2020

Numbers whose odd part is a prime power (A246655). - Amiram Eldar, Jul 08 2020

Numbers of the form 2^r * p^q  with p an odd prime (A065091), r >= 0, q >= 1. - Bernard Schott, Dec 14 2020

LINKS

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

MATHEMATICA

Select[Range[104], PrimePowerQ[#/2^IntegerExponent[#, 2]] &] (* Amiram Eldar, Jul 08 2020 *)

PROG

(PARI) isA336101(n) = (1==omega(n>>valuation(n, 2))); \\ Antti Karttunen, Jul 08 2020

CROSSREFS

Cf. A000265, A001221, A246655.

Positions of ones in A005087.

Subsequence of A267895.

Subsequences: A007283 (3*2^n), A020714 (5*2^n), A005009 (7*2^n), A005015 (11*2^n), A005029 (13*2^n), A038550 (p*2^n, p odd prime), A065091 (odd primes), A061345 \ {1} (odd prime powers).

Sequence in context: A277727 A080943 A052294 * A267895 A216189 A191916

Adjacent sequences:  A336098 A336099 A336100 * A336102 A336103 A336104

KEYWORD

nonn,easy

AUTHOR

Peter Munn, Jul 08 2020

STATUS

approved

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Last modified October 27 12:08 EDT 2021. Contains 348276 sequences. (Running on oeis4.)