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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
OFFSET
1,1
LINKS
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
KEYWORD
nonn
AUTHOR
STATUS
approved