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A230810 Smallest of 3 consecutive odd numbers that are primes or strong pseudoprime to base 2. 2

%I

%S 3,3465253618399,374166120095639,12959269432331237,44202753561285409,

%T 1640293473202755797,1640293473202755799,10623546148468360249

%N Smallest of 3 consecutive odd numbers that are primes or strong pseudoprime to base 2.

%C Since a(7) = a(6) + 2, the number a(6) = 1640293473202755797 actually starts a sequence of four consecutive odd numbers which are prime or strong pseudoprimes to base 2. - _M. F. Hasler_, Dec 08 2016

%H S. S. Gupta, <a href="http://www.shyamsundergupta.com/canyoufind.htm">Can You Find no. 48</a>, Oct. 2016.

%e 3465253618399 is in sequence because 3465253618399, 3465253618401, 3465253618403 is a set of 3 consecutive odd number where 3465253618401 is strong pseudoprime base 2 and others are prime.

%Y Cf. A001262, A001567, A230667, A230808.

%K nonn,hard,more

%O 1,1

%A _Shyam Sunder Gupta_, Oct 30 2013

%E Edited by _M. F. Hasler_, Dec 08 2016

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Last modified October 19 04:40 EDT 2019. Contains 328211 sequences. (Running on oeis4.)