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A064166 Composite numbers the sum of the digits in the prime factors of which, with repetition, is prime. 1
6, 10, 12, 28, 33, 39, 40, 45, 46, 48, 51, 54, 55, 56, 57, 58, 63, 66, 75, 80, 82, 85, 90, 91, 93, 94, 96, 102, 108, 111, 130, 133, 147, 154, 156, 159, 166, 172, 175, 177, 178, 182, 184, 190, 207, 210, 213, 217, 219, 220, 224, 226, 228, 232, 237, 238, 244, 245 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Harvey P. Dale, Table of n, a(n) for n = 0..1000

EXAMPLE

220 is included because 220 = 2*2*5*11 and 2+2+5+1+1 = 11, which is prime.

MATHEMATICA

cnpQ[n_]:=CompositeQ[n]&&PrimeQ[Total[Flatten[IntegerDigits/@(Table[ #[[1]], #[[2]]]&/@FactorInteger[n])]]]; Select[Range[250], cnpQ] (* Harvey P. Dale, Sep 15 2016 *)

CROSSREFS

Sequence in context: A101086 A297620 A074924 * A107371 A213428 A006187

Adjacent sequences:  A064163 A064164 A064165 * A064167 A064168 A064169

KEYWORD

nonn,base

AUTHOR

Harvey P. Dale, Sep 19 2001

STATUS

approved

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Last modified November 28 20:27 EST 2020. Contains 338755 sequences. (Running on oeis4.)