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A074979
Primes for which the two closest primes are smaller.
8
113, 139, 181, 199, 241, 283, 293, 317, 467, 509, 523, 577, 619, 661, 773, 829, 839, 863, 887, 953, 1021, 1039, 1069, 1129, 1237, 1307, 1327, 1381, 1459, 1499, 1583, 1627, 1637, 1669, 1699, 1759, 1789, 1879, 1913, 1951, 2003, 2039, 2089, 2113, 2143
OFFSET
1,1
LINKS
EXAMPLE
The two closest primes to 113 are 109 (difference = 4) and 107 (difference = 6). Both 109 and 107 are 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, 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, 330}]
Select[Partition[Prime[Range[400]], 4, 1], #[[3]]-#[[1]]<#[[4]]-#[[3]]&][[All, 3]] (* Harvey P. Dale, Aug 11 2021 *)
KEYWORD
nonn
AUTHOR
Neil Fernandez, Oct 10 2002
EXTENSIONS
Edited by Robert G. Wilson v, Oct 11 2002
STATUS
approved