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A167609
Primes which are not the sum of two consecutive nonprimes A141468.
1
2, 3, 7, 11, 13, 23, 37, 47, 59, 61, 73, 83, 107, 157, 167, 179, 193, 227, 263, 277, 313, 347, 359, 383, 397, 421, 457, 467, 479, 503, 541, 563, 587, 613, 661, 673, 719, 733, 757, 839, 863, 877, 887, 983, 997, 1019, 1093, 1153, 1187, 1201, 1213, 1237, 1283
OFFSET
1,1
COMMENTS
2, and primes p such that floor(p/2) or ceiling(p/2) is prime, but not both. - Robert Israel, Jan 23 2024
LINKS
MAPLE
filter:= proc(n) if n mod 4 = 1
then isprime(n) and isprime((n+1)/2)
else isprime(n) and isprime((n-1)/2)
fi end proc:
2, 3, op(select(filter, [seq(i, i=7 .. 10000, 2)])); # Robert Israel, Jan 23 2024
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
Entries checked by R. J. Mathar, May 30 2010
STATUS
approved