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A230715
Smallest numbers in a set of 4 consecutive odd numbers that are primes or pseudoprime (base 2).
3
641, 656597, 6212357, 18958567877, 287468425241, 626160901277, 634038307447, 1395494019917, 1925525109197, 1960708164797, 1962378065897, 1977370759361, 2788325761547, 3032013857177, 4846359321103, 6877227801077, 11927878640383, 20835183400303, 22298617759877
OFFSET
1,1
EXAMPLE
656597 is in sequence because 656597, 656599, 656601, 656603 is a set of 4 consecutive odd number where 656601 is pseudoprime base 2 and others are prime.
PROG
(PARI) \\ Import A001567 into the vector v
for(i=1, #v, start=stop=v[i]; while(ok(start-=2), ); while(ok(stop+=2), ); while(stop-start>9, print1(start+=2, ", "))) \\ Charles R Greathouse IV, Oct 28 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Shyam Sunder Gupta, Oct 28 2013
STATUS
approved