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A348098 Number k such that k and k+1 both have an equal number of unitary and nonunitary prime divisors (A348097). 4
44, 75, 98, 116, 135, 147, 152, 171, 175, 188, 207, 244, 296, 332, 351, 368, 375, 387, 404, 423, 424, 507, 548, 567, 603, 604, 639, 656, 711, 724, 775, 832, 844, 847, 872, 891, 908, 927, 931, 963, 1016, 1028, 1052, 1075, 1083, 1107, 1183, 1215, 1250, 1251, 1268 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
EXAMPLE
44 is a term since 44 = 2^2 * 11 and 44 + 1 = 45 = 3^2 * 5 both have one unitary prime divisor and one nonunitary prime divisor.
MATHEMATICA
q[n_] := n == 1 || Count[(e = FactorInteger[n][[;; , 2]]), 1] == Length[e]/2; Select[Range[10^3], q[#] && q[# + 1] &]
CROSSREFS
Subsequence of A348097.
Cf. A335328.
Sequence in context: A242515 A156812 A171665 * A348076 A348345 A049103
KEYWORD
nonn
AUTHOR
Amiram Eldar, Sep 30 2021
STATUS
approved

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Last modified March 3 17:23 EST 2024. Contains 370512 sequences. (Running on oeis4.)