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A008471
Exactly 3 out of 10m+1, 10m+3, 10m+7, 10m+9 are primes.
6
4, 7, 13, 22, 31, 43, 46, 61, 64, 85, 88, 103, 106, 109, 130, 142, 145, 160, 166, 169, 178, 199, 238, 268, 271, 316, 367, 376, 391, 400, 409, 415, 421, 451, 472, 478, 493, 523, 541, 544, 547, 550, 574
OFFSET
1,1
LINKS
V. Raman, Table of n, a(n) for n = 1..10000 (first 1000 terms from Harvey P. Dale)
MATHEMATICA
m3Q[m_]:=Module[{c=10m}, Count[{c+1, c+3, c+7, c+9}, _?PrimeQ]==3]; Select[ Range[ 600], m3Q] (* Harvey P. Dale, Dec 24 2011 *)
PROG
(Magma) [n: n in [1..600] | #PrimesInInterval(10*n+1, 10*n+9) eq 3]; // Bruno Berselli, Sep 04 2012
CROSSREFS
KEYWORD
nonn
STATUS
approved