A105049 a(n) is the smallest prime p such that p+n! is prime and p differs from all a(i), i<n.

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.

Links

Table of n, a(n) for n=1..60.

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

Adjacent sequences: A105046 A105047 A105048 * A105050 A105051 A105052

Keyword

nonn

Author

R. J. Mathar, Aug 22 2007

Status

approved