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A231879 Numbers n such that bigomega(n)^2 (cf. A001222) does not divide n. 2
1, 6, 8, 9, 10, 12, 14, 15, 20, 21, 22, 24, 25, 26, 28, 30, 32, 33, 34, 35, 36, 38, 39, 40, 42, 44, 46, 48, 49, 50, 51, 52, 54, 55, 56, 57, 58, 60, 62, 64, 65, 66, 68, 69, 70, 72, 74, 75, 76, 77, 78, 80, 81, 82, 84, 85, 86, 87, 88, 90, 91, 92, 93, 94, 95, 96, 98, 100, 102, 104, 105, 106, 108, 110, 111, 112, 114, 115 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Contains all semiprimes (A001358) except 4. - Ivan Neretin, Apr 05 2016
LINKS
MATHEMATICA
Join[{1}, Select[Range[2, 115], ! Divisible[#, PrimeOmega[#]^2] &]] (* Ivan Neretin, Apr 05 2016 *)
PROG
(PARI) lista(nn) = {print1(1, ", "); for(n=2, nn, if(n % bigomega(n)^2 != 0, print1(n, ", "))); } \\ Altug Alkan, Apr 05 2016
CROSSREFS
Sequence in context: A054047 A056653 A285847 * A062973 A070162 A030550
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Nov 17 2013
STATUS
approved

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Last modified March 28 11:59 EDT 2024. Contains 371254 sequences. (Running on oeis4.)