This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 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

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified October 16 06:20 EDT 2019. Contains 328048 sequences. (Running on oeis4.)