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A062713
Numbers k such that the sum of the digits of k is a prime factor of k.
2
2, 3, 5, 7, 12, 20, 21, 30, 50, 70, 102, 110, 111, 120, 133, 140, 200, 201, 209, 210, 230, 247, 300, 308, 320, 322, 364, 407, 410, 476, 481, 500, 506, 511, 605, 629, 700, 704, 715, 782, 803, 832, 874, 902, 935, 1002, 1010, 1011, 1015, 1020, 1040, 1066, 1088
OFFSET
1,1
LINKS
EXAMPLE
2 is an element since 2 is a prime factor of 2; 12 is an element since 1 + 2 = 3 and 3 is a prime factor of 12.
MATHEMATICA
sdpfQ[n_]:=MemberQ[Transpose[FactorInteger[n]][[1]], Total[ IntegerDigits[ n]]]; Select[Range[2, 1100], sdpfQ] (* Harvey P. Dale, Sep 24 2012 *)
PROG
(PARI) ok(k)={my(s=sumdigits(k)); k % s==0 && isprime(s)} \\ Andrew Howroyd, Jun 28 2018
CROSSREFS
Sequence in context: A018065 A048818 A318745 * A334630 A086108 A052430
KEYWORD
nonn,base,easy
AUTHOR
Lisa O Coulter (lisa_coulter(AT)my-deja.com), Jul 14 2001
EXTENSIONS
Corrected and extended by Larry Reeves (larryr(AT)acm.org) and Dean Hickerson, Jul 16 2001
STATUS
approved