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 A230808 Smallest sets of 3 consecutive odd numbers that are primes or pseudoprime (base 2). The initial odd number is listed. 2
 3, 641, 643, 4369, 25759, 33149, 87249, 129917, 157637, 212419, 332947, 451901, 656597, 656599, 831405, 1489665, 1608461, 2113665, 3020357, 3370637, 6212357, 6212359, 19092917, 31880577, 34487597, 38790749, 63560683, 81612105, 84028407, 86559045, 274014885 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Shyam Sunder Gupta, Table of n, a(n) for n = 1..5001 Jan Feitsma, Tables of pseudoprimes and related data EXAMPLE 641 is in sequence because 641, 643, 645 is a set of 3 consecutive odd number where 645 is pseudoprime base 2 and others are prime. CROSSREFS Cf. A001567, A230559, A228575, A230668, A230715. Sequence in context: A229688 A287890 A091261 * A158600 A092301 A229668 Adjacent sequences:  A230805 A230806 A230807 * A230809 A230810 A230811 KEYWORD nonn AUTHOR Shyam Sunder Gupta, Oct 30 2013 STATUS approved

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Last modified October 18 08:08 EDT 2019. Contains 328146 sequences. (Running on oeis4.)