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A160058
Primes whose distance to both nearest neighbor primes is not of the form 2^k.
1
53, 157, 173, 211, 251, 257, 263, 293, 331, 337, 373, 509, 541, 547, 557, 563, 577, 587, 593, 607, 631, 653, 733, 787, 797, 839, 947, 953, 977, 997, 1039, 1069, 1103, 1123, 1129, 1181, 1187, 1223, 1237, 1249, 1259, 1327, 1361, 1367, 1399, 1409, 1459, 1471
OFFSET
1,1
COMMENTS
Intersection with A061771 yields an empty set. - R. J. Mathar, May 21 2009
LINKS
Klaus Lange, About a virtual subset, Apr 30, 2009.
MAPLE
isA000079 := proc(n) if nops(numtheory[factorset](n)) > 1 then false; elif n mod 2 <> 0 then false; else true; fi; end: isA160058 := proc(p) o := prevprime(p) ; q := nextprime(p) ; if isprime(p) and not isA000079(q-p) and not isA000079(p-o) then true; else false; fi; end: for n from 2 to 1000 do p := ithprime(n) ; if isA160058(p) then printf("%d, ", p) ; fi; od: # R. J. Mathar, May 21 2009
MATHEMATICA
n2kQ[n_]:=Module[{d=Differences[n]}, !IntegerQ[Log[2, First[d]]] && !IntegerQ[ Log[ 2, Last[d]]]]; Transpose[Select[Partition[Prime[ Range[ 300]], 3, 1], n2kQ]][[2]] (* Harvey P. Dale, Mar 05 2014 *)
PROG
(PARI) t=0; p=2; forprime(q=3, 999, t*(t=q-p-1<<valuation(q-p, 2)) & print1(p", "); p=q)
CROSSREFS
Cf. A000040. This is a proper subsequence of A137869.
Sequence in context: A044385 A044766 A342450 * A353136 A053070 A140655
KEYWORD
nonn
AUTHOR
Jonathan Vos Post, May 01 2009
EXTENSIONS
More terms from M. F. Hasler, May 02 2008
Edited by N. J. A. Sloane, May 02 2009, based on comments from M. F. Hasler
More terms from R. J. Mathar, May 21 2009
STATUS
approved