A175758 - OEIS

A175758

Numbers n with property that arithmetic mean of its digits is both an integer and one of the prime factors of n.

2, 3, 5, 7, 15, 22, 24, 33, 40, 42, 51, 55, 60, 77, 108, 114, 117, 126, 132, 135, 144, 150, 153, 162, 171, 180, 195, 204, 207, 216, 222, 225, 234, 240, 243, 252, 261, 270, 285, 306, 312, 315, 324, 330, 333, 342, 351, 360, 375, 399, 402, 405, 414, 420, 423, 432

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

EXAMPLE

15 is in the list because (1+5)/2=3 and 3 is a prime factor of 15.

MATHEMATICA

ipfQ[n_]:=Module[{m=Mean[IntegerDigits[n]]}, IntegerQ[m]&&MemberQ[ FactorInteger[ n][[All, 1]], m]]; Select[Range[2, 500], ipfQ] (* Harvey P. Dale, Feb 15 2020 *)

CROSSREFS

Cf. A027746, A175688.

Sequence in context: A331037 A228652 A157833 * A383801 A383493 A151531

Adjacent sequences: A175755 A175756 A175757 * A175759 A175760 A175761

KEYWORD

nonn,base

AUTHOR

Juri-Stepan Gerasimov, Aug 28 2010, Aug 29 2010

EXTENSIONS

399 inserted by D. S. McNeil, Sep 27 2010

STATUS

approved