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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.
1
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
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
KEYWORD
easy,base,nonn
AUTHOR
Felice Russo, Aug 13 2001
EXTENSIONS
Better description and more terms from Matthew Conroy, Aug 14 2001
STATUS
approved