

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
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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(t1), D))>= 3
end proc:
select(filter, [$1..1000]);


PROG

(PARI) isok(m) = sumdiv(m, d, isprime(d1)) >= 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



