The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A176312 Numbers that are the products of two single (or isolated or non-twin) primes. 3
 4, 46, 74, 94, 106, 134, 158, 166, 178, 194, 226, 254, 262, 314, 326, 334, 346, 422, 446, 466, 502, 514, 526, 529, 554, 586, 614, 634, 662, 674, 706, 718, 734, 746, 758, 766, 778, 794, 802, 818, 851, 878, 886, 898, 914, 934, 958, 974, 982, 998, 1006, 1018, 1081 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Amiram Eldar, Table of n, a(n) for n = 1..10000 MAPLE isA007510 := proc(n) isprime(n) and not isprime(n+2) and not isprime(n-2) ; simplify(%) ; end proc: isA176312 := proc(n) for d in numtheory[divisors](n) do if isA007510(d) and isA007510(n/d) then return true; end if; end do: return false; end proc: for n from 1 to 1200 do if isA176312(n) then printf("%d, ", n) ; end if; end do: # R. J. Mathar, Apr 20 2010: MATHEMATICA Select[Range[1000], PrimeOmega[#] == 2 && AllTrue[FactorInteger[#][[;; , 1]], ! PrimeQ[#1 - 2] && ! PrimeQ[#1 + 2] &] &] (* Amiram Eldar, Nov 30 2020 *) CROSSREFS Cf. A007510. Sequence in context: A222899 A119729 A134110 * A309450 A119046 A273776 Adjacent sequences:  A176309 A176310 A176311 * A176313 A176314 A176315 KEYWORD nonn AUTHOR Juri-Stepan Gerasimov, Apr 15 2010 EXTENSIONS Entries checked by R. J. Mathar, Apr 20 2010 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 April 20 06:59 EDT 2021. Contains 343125 sequences. (Running on oeis4.)