A160058 Primes whose distance to both nearest neighbor primes is not of the form 2^k.
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
Keywords
Links
- Harvey P. Dale, Table of n, a(n) for n = 1..1000
- Klaus Lange, About a virtual subset, Apr 30, 2009.
Programs
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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
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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 *) -
PARI
t=0;p=2;forprime(q=3,999, t*(t=q-p-1<
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
Comments