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%I #8 May 23 2024 04:26:42
%S 1,1,2,2,2,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,4,4,4,4,5,5,
%T 5,5,5,5,5,5,5,5,5,5,6,6,6,7,7,7,7,7,7,7,7,7,7,7,7,8,8,8,9,9,9,9,9,9,
%U 9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,10,10,10,10,10
%N a(n) = |S(n)| where S(n) = {i : 1 <= i <= n and 4*i-1 and 8*i-1 are primes}.
%C Number of Lucasian primes that do not exceed 4*n-1. [Corrected by _Amiram Eldar_, May 23 2024]
%t Accumulate[Table[Boole[And @@ PrimeQ[{4, 8}*i - 1]], {i, 1, 100}]] (* _Amiram Eldar_, May 23 2024 *)
%Y Cf. A002515, A101788.
%K easy,nonn
%O 1,3
%A Douglas Stones (dssto1(AT)student.monash.edu.au), Dec 16 2004
%E Name corrected by _Amiram Eldar_, May 23 2024