A063738 Numbers n such that sum of digits of n is equal to the product of the digits of the sum of the prime factors of n, counted with multiplicity.

2, 3, 4, 5, 7, 27, 46, 52, 93, 117, 121, 143, 170, 174, 187, 228, 235, 240, 242, 250, 259, 341, 408, 451, 504, 512, 671, 682, 684, 720, 754, 759, 781, 810, 867, 888, 1017, 1120, 1143, 1155, 1173, 1247, 1272, 1276, 1357, 1362, 1377, 1449, 1456, 1524, 1537, 1564

Offset

1,1

Links

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

Example

27: 2+7=9, 27= 3 * 3 * 3, 3+3+3=9; 170: 170=2*5*17, 1+7+0=8, 2+5+17=24, 2*4=8.

Mathematica

sdQ[n_]:=Total[IntegerDigits[n]]==Times@@IntegerDigits[Total[ Flatten[ Table[ #[[1]], {#[[2]]}]&/@FactorInteger[n]]]]; Select[Range[2, 2000], sdQ] (* Harvey P. Dale, Mar 01 2016 *)

Crossrefs

Sequence in context: A203615 A273932 A270831 * A063737 A338121 A278342

Adjacent sequences: A063735 A063736 A063737 * A063739 A063740 A063741

Keyword

easy,base,nonn

Author

Felice Russo, Aug 13 2001

Extensions

Better description and more terms from Matthew Conroy, Aug 14 2001

Status

approved