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Search: id:A094709
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| A094709 |
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Smallest k such that prime(n)# - k and prime(n)# + k are primes, where prime(n)# = A002110(n). |
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3
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| 0, 1, 1, 13, 1, 17, 59, 23, 79, 101, 83, 239, 71, 149, 367, 73, 911, 313, 373, 523, 313, 331, 197, 101, 1493, 523, 293, 577, 2699, 1481, 1453, 5647, 647, 419, 757, 4253, 509, 239, 10499, 191, 4013, 2659, 617, 6733, 1297, 971
(list; graph; listen)
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OFFSET
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1,4
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COMMENT
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a(n) = A002110(n) - A094710(n) = A094711(n) - A002110(n),
Goldbach's conjecture implies that a(n) is defined for all n. - David Wasserman (dwasserm(AT)earthlink.net), May 31 2007
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LINKS
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David Wasserman, Table of n, a(n) for n = 1..250
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EXAMPLE
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a(4)=13 because prime(4)=7, 7# = 2*3*5*7 = 210 and 210-13 and 210+13 are primes.
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MATHEMATICA
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pc[n_]:=Module[{x=0, i=0}, Do[If[PrimeQ[n-i]&&PrimeQ[n+i], x=i; Break[]], {i, 9!}]; x]; r=2; lst={}; Do[p=Prime[n]; r*=p; AppendTo[lst, pc[r]], {n, 2, 2*4!}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Jun 14 2009]
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CROSSREFS
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Cf. A078611.
Sequence in context: A010236 A058018 A037283 this_sequence A040181 A123187 A046733
Adjacent sequences: A094706 A094707 A094708 this_sequence A094710 A094711 A094712
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KEYWORD
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nonn
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AUTHOR
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Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), May 21 2004
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EXTENSIONS
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More terms from Don Reble (djr(AT)nk.ca), May 27 2004
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