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A339424 Composite numbers k such that A339423(k) divides k. 2
4, 6, 9, 10, 12, 14, 15, 21, 22, 25, 26, 33, 34, 35, 36, 38, 39, 46, 49, 51, 55, 56, 57, 58, 62, 65, 69, 74, 77, 82, 85, 86, 87, 91, 93, 94, 95, 106, 108, 111, 115, 118, 119, 121, 122, 123, 129, 133, 134, 141, 142, 143, 145, 146, 155, 158, 159, 161, 166, 169, 177, 178, 183, 185, 187, 194, 201 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

EXAMPLE

a(5)=12 = 2*2*3 is a term because 2 + 2*2 = 6 divides 12.

MAPLE

filter:= proc(n)

  local F, T, P, j;

  if isprime(n) then return false fi;

  F:= sort(map(t -> t[1]$t[2], ifactors(n)[2]));

  T:= 0; P:= 1;

  for j from 1 to nops(F)-1 do

    P:= P*F[j];

    T:= T+P;

  od;

  n mod T = 0

end proc:

select(filter, [$4..1000]);

CROSSREFS

Cf. A002808, A339423.

Union of A001358 and A339425.

Sequence in context: A325270 A051278 A328028 * A175127 A174166 A171401

Adjacent sequences:  A339421 A339422 A339423 * A339425 A339426 A339427

KEYWORD

nonn

AUTHOR

J. M. Bergot and Robert Israel, Dec 03 2020

STATUS

approved

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Last modified September 20 16:50 EDT 2021. Contains 347586 sequences. (Running on oeis4.)