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A186721 Numbers n such that n, 4n + 1 and 6n + 1 are all prime. 1
3, 7, 13, 37, 73, 277, 373, 577, 727, 853, 1033, 1063, 1327, 1423, 1453, 1567, 1777, 1987, 2293, 2677, 2767, 3037, 3163, 3307, 3457, 4273, 4447, 4993, 5197, 5557, 6247, 6673, 7573, 8353, 8893, 9067, 9397, 9463, 9547, 9613, 10303, 10903, 12007, 12973, 13177, 14083 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Subsequence of A023212.

LINKS

Table of n, a(n) for n=1..46.

MATHEMATICA

Join[{3}, Select[Range[7, 20000, 6], PrimeQ[#] && PrimeQ[4# + 1] && PrimeQ[6# + 1] &]]

CROSSREFS

Cf. A023212.

Sequence in context: A106057 A049492 A166283 * A177945 A147448 A146449

Adjacent sequences:  A186718 A186719 A186720 * A186722 A186723 A186724

KEYWORD

nonn

AUTHOR

Zak Seidov, Jan 21 2012

STATUS

approved

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Last modified January 22 16:29 EST 2020. Contains 331152 sequences. (Running on oeis4.)