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A108610 Semiprimes with prime sum of decimal digits and prime sum of prime factors. 1
34, 58, 142, 214, 274, 298, 382, 454, 478, 562, 694, 838, 922, 1042, 1138, 1198, 1282, 1318, 1642, 1714, 2038, 2098, 2122, 2182, 2302, 2458, 2638, 2854, 2902, 2962, 3334, 3394, 3442, 3574, 3754, 3862, 4054, 4162, 4258, 4474, 4618, 4762, 5314, 5374, 5422 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Intersection of A108605 and A108606. All terms are even. Cf. A001358 semiprimes, A101605 3-almost primes, A108605 semiprimes with prime sum of factors, A108606 semiprimes with prime sum of digits.

LINKS

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

EXAMPLE

34=2*17 (semiprime), with 3+4=7 and 2+17=19 both prime.

MATHEMATICA

psddQ[n_]:=!IntegerQ[Sqrt[n]]&&PrimeOmega[n]==2&&PrimeQ[Total[ IntegerDigits[n]]] && PrimeQ[Total[Transpose[FactorInteger[n]][[1]]]]; Select[Range[5500], psddQ] (* Harvey P. Dale, Oct 03 2012 *)

CROSSREFS

Cf. A001358, A101605, A108605, A108606.

Sequence in context: A103558 A103686 A211715 * A261314 A119454 A259952

Adjacent sequences:  A108607 A108608 A108609 * A108611 A108612 A108613

KEYWORD

nonn,base

AUTHOR

Zak Seidov, Jun 12 2005

STATUS

approved

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Last modified August 20 13:04 EDT 2017. Contains 290835 sequences.