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A168473 Primes in A168472. 1
181, 293, 907, 2311, 2971, 3547, 4019, 4523, 5651, 7103, 7753, 8419, 14489, 15443, 17417, 18097, 18443, 22171, 31123, 32063, 41611, 42683, 44851, 48761, 67829, 69221, 79273, 98047, 103903, 107347, 114407, 122597, 132967, 149909, 154081 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

MAPLE

N:= 10^4: # to get all a(n) where A006881(n) < N

Primes:= select(isprime, [2, seq(2*k+1, k=1..floor(N/2))]):

L:= sort(convert({seq(seq(p*q, q=Primes[1..ListTools:-BinaryPlace(Primes, N/p)]), p=Primes)} minus {seq(p^2, p=Primes)}, list)):

A168472:= ListTools:-PartialSums(L):

select(isprime, A168472); # Robert Israel, Mar 20 2019

MATHEMATICA

f[n_]:=Last/@FactorInteger[n]=={1, 1}; s=0; lst={}; Do[If[f[n], If[PrimeQ[s+=n], AppendTo[lst, s]]], {n, 7!}]; lst

With[{nn=50}, Select[Accumulate[Union[Times@@@Subsets[Prime[Range[2nn]], {2}]]], PrimeQ, nn]] (* Harvey P. Dale, Aug 08 2013 *)

CROSSREFS

Cf. A168472.

Sequence in context: A142312 A020360 A238670 * A142920 A142058 A138397

Adjacent sequences:  A168470 A168471 A168472 * A168474 A168475 A168476

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, Nov 26 2009

STATUS

approved

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Last modified October 26 02:14 EDT 2021. Contains 348256 sequences. (Running on oeis4.)