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 A341099 Numbers divisible by at least three members of A008864. 2
 12, 18, 24, 30, 32, 36, 40, 42, 48, 54, 56, 60, 64, 72, 80, 84, 88, 90, 96, 102, 104, 108, 112, 114, 120, 126, 128, 132, 136, 138, 140, 144, 150, 152, 156, 160, 162, 168, 174, 176, 180, 186, 192, 196, 198, 200, 204, 208, 210, 216, 220, 222, 224, 228, 234, 240, 248, 252, 256, 258, 264, 270, 272 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Numbers divisible by p+1 for at least three primes p. Numbers k with A072627(k) >= 3. Every positive multiple of a term is a term. LINKS Robert Israel, Table of n, a(n) for n = 1..10000 EXAMPLE a(4) = 30 is a term because it is divisible by 2+1=3, 5+1=6 and 29+1=30. MAPLE filter:= proc(n) local D;   D:= convert(numtheory:-divisors(n), list);   numboccur(true, map(t -> isprime(t-1), D))>= 3 end proc: select(filter, [\$1..1000]); PROG (PARI) isok(m) = sumdiv(m, d, isprime(d-1)) >= 3; \\ Michel Marcus, Feb 05 2021 CROSSREFS Cf. A005101, A005835, A008864, A072627. Sequence in context: A162151 A056773 A297925 * A175837 A136446 A074726 Adjacent sequences:  A341096 A341097 A341098 * A341100 A341101 A341102 KEYWORD nonn AUTHOR J. M. Bergot and Robert Israel, Feb 04 2021 STATUS approved

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Last modified April 19 00:03 EDT 2021. Contains 343098 sequences. (Running on oeis4.)