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A105049
a(n) is the smallest prime p such that p+n! is prime and p differs from all a(i), i<n.
2
2, 3, 5, 7, 11, 13, 19, 23, 17, 41, 29, 43, 67, 71, 149, 73, 31, 37, 89, 53, 47, 127, 97, 131, 107, 59, 137, 101, 223, 163, 241, 79, 139, 103, 61, 577, 311, 151, 269, 173, 211, 167, 109, 191, 239, 521, 233, 83, 383, 337, 271, 827, 449, 443, 229, 157, 179, 283, 293, 277
OFFSET
1,1
COMMENTS
A variant of A130807.
If the requirement is dropped that a(n) be distinct from earlier primes in the list, the sequence becomes 2, 3, 5, 5, 7, 7, 11, 23, 17, 11, 17, 29, 67, 19, 43, 23, 31, 37, 89,.. which presumably duplicates A037153.
MAPLE
A105049 := proc(nmin) local i, a, iused; a := [] ; iused := {} ; for n from 1 to nmin do i := 1; while not isprime(ithprime(i)+n!) or i in iused do i := i+1 ; od; iused := iused union {i} ; a := [op(a), ithprime(i)] ; od ; RETURN(a) ; end: A105049(80);
CROSSREFS
Sequence in context: A322527 A181160 A316968 * A057447 A095074 A042987
KEYWORD
nonn
AUTHOR
R. J. Mathar, Aug 22 2007
STATUS
approved