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A050704 Composite numbers with property that n minus sum of prime factors of n is prime. 10
8, 9, 10, 12, 14, 15, 20, 21, 26, 28, 33, 35, 38, 39, 40, 44, 48, 51, 54, 56, 62, 65, 68, 69, 76, 77, 80, 86, 88, 91, 93, 95, 96, 111, 112, 116, 122, 123, 124, 129, 133, 136, 146, 148, 152, 159, 161, 176, 188, 189, 198, 201, 203, 206, 209, 210, 213, 215, 217, 218 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Prime factors are totaled with multiplicity, e.g., 8 = 2*2*2 so the sum of the prime factors of 8 = 6. - Harvey P. Dale, Jun 14 2011

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

EXAMPLE

E.g., 161 = 7*23; 161 - (7+23) = 161 - 30 = 131, which is prime.

MATHEMATICA

Select[Range[250], PrimeQ[#-Total[Times@@@FactorInteger[#]]]&] (* Harvey P. Dale, Jun 14 2011 *)

CROSSREFS

Cf. A050703-A050710.

Sequence in context: A152870 A181723 A078893 * A024884 A031009 A120184

Adjacent sequences:  A050701 A050702 A050703 * A050705 A050706 A050707

KEYWORD

nonn,nice

AUTHOR

Patrick De Geest, Aug 15 1999

STATUS

approved

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Last modified November 14 15:06 EST 2019. Contains 329126 sequences. (Running on oeis4.)