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A143321
Positive integers k whose sum of distinct prime divisors divides k+1.
2
15, 20, 24, 35, 54, 95, 98, 104, 119, 135, 143, 144, 160, 189, 207, 209, 224, 287, 319, 323, 324, 351, 363, 375, 377, 384, 390, 459, 464, 527, 539, 559, 608, 779, 845, 864, 875, 899, 923, 989, 999, 1000, 1007, 1029, 1189, 1199, 1215, 1280, 1343, 1349, 1375
OFFSET
1,1
LINKS
EXAMPLE
The distinct primes dividing 24 are 2 and 3, since 24 is factored as 2^3 *3^1. 2 + 3 = 5 is a divisor of 24 + 1 = 25. So 24 is a term of this sequence.
MAPLE
with(numtheory): a:= proc(n) local f: f:=factorset(n); if `mod`(n+1, add(i, i=f))=0 then n end if end proc: seq(a(n), n=2..1200); # Emeric Deutsch, Aug 14 2008
MATHEMATICA
Select[Range[2, 1500], Divisible[#+1, Total[FactorInteger[#][[All, 1]]]]&] (* Harvey P. Dale, Aug 27 2022 *)
PROG
(PARI) is(n) = n > 1 && (n + 1) % vecsum(factor(n)[, 1]) == 0 \\ David A. Corneth, Mar 10 2019
CROSSREFS
KEYWORD
nonn
AUTHOR
Leroy Quet, Aug 07 2008
EXTENSIONS
More terms from Emeric Deutsch, Aug 14 2008
More terms from Max Alekseyev, Mar 10 2009
STATUS
approved