A074982 Primes for which the three closest primes are smaller.

113, 199, 317, 467, 829, 863, 887, 1129, 1307, 1327, 1637, 1669, 1879, 1951, 2089, 2251, 2311, 2477, 2557, 2803, 2971, 3229, 3259, 3271, 3373, 3469, 3739, 3947, 4027, 4139, 4297, 4463, 4523, 4733, 5023, 5119, 5237, 5351, 5449, 5483, 5531, 5591, 5659

Offset

1,1

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Example

The three closest primes to 113 are 109 (difference = 4), 107 (difference = 6) and 103 (difference = 10). 109, 107 and 103 are all smaller than 113, so 113 is in the list.

Mathematica

NextPrim[n_] := Block[{k = n + 1}, While[ !PrimeQ[k], k++ ]; k]; ps = {0, 0, 0, 0, 1}; Do[ps = Drop[ps, 1]; ps = Append[ps, NextPrim[ ps[[ -1]]]]; If[ ps[[ -1]] - ps[[ -2]] > ps[[ -2]] - ps[[1]], Print[ ps[[ -2]]]], {n, 1, 756}]
Select[Partition[Prime[Range[800]], 5, 1], #[[4]]-#[[1]]<#[[5]]-#[[4]]&][[All, 4]] (* Harvey P. Dale, Mar 14 2018 *)

Crossrefs

Cf. A001223, A074979, A075030, A075037, A075038, A075043, A075050 and A075051.

Sequence in context: A056710 A124585 A173594 * A094932 A173595 A142276

Adjacent sequences: A074979 A074980 A074981 * A074983 A074984 A074985

Keyword

nonn

Author

Neil Fernandez, Oct 10 2002

Extensions

Edited by Robert G. Wilson v, Oct 11 2002

Status

approved