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A271909
Numbers k such that k and 3*k+1 have the same number of prime divisors (including multiplicities).
2
2, 15, 35, 38, 39, 55, 62, 63, 82, 86, 87, 91, 105, 106, 111, 114, 115, 118, 119, 134, 142, 147, 155, 159, 178, 187, 189, 194, 212, 218, 225, 226, 235, 238, 254, 258, 259, 267, 268, 275, 278, 282, 287, 295, 298, 299, 310, 314, 319, 326, 327, 334, 335, 338, 339, 343
OFFSET
1,1
LINKS
FORMULA
Numbers k such that bigomega(k) = bigomega(3*k+1).
MAPLE
with(numtheory): A271909:=n->`if`(bigomega(n)=bigomega(3*n+1), n, NULL): seq(A271909(n), n=1..800); # Wesley Ivan Hurt, Apr 22 2016
MATHEMATICA
Select[Range[350], PrimeOmega[#] == PrimeOmega[3 # + 1] &] (* Amiram Eldar, Apr 02 2020 *)
CROSSREFS
Sequence in context: A300765 A300635 A301357 * A346641 A075541 A075542
KEYWORD
nonn
AUTHOR
Benjamin Przybocki, Apr 22 2016
STATUS
approved