

A132861


Smallest number at distance 3n from nearest prime (variant 2).


0



2, 26, 53, 532, 211, 1342, 2179, 15704, 16033, 31424, 24281, 31430, 31433, 155960, 58831, 360698, 206699, 370312, 370315, 492170, 1357261, 1357264, 1357267, 2010802, 2010805, 4652428
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OFFSET

0,1


COMMENTS

Let f(m) be the distance to the nearest prime as defined in A051700(m). Then a(n) = min { m: f(m)= 3n }. A132470 uses A051699(m) to define the distance. a(n) <= A132470(n) because here primes at the start or end of a prime gap of size 3n may be picked, which would be discarded in A132470 for n>0; this gives a chance to minimize m here further than in A132470.


LINKS

Table of n, a(n) for n=0..25.


FORMULA

a(n) = min {m : A051700(m) = 3n}.
a(n)=A051652(3*n). [From R. J. Mathar, Jul 22 2009]


MAPLE

A051700 := proc(m) if m <= 2 then op(m+1, [2, 1, 1]) ; else min(nextprime(m)m, mprevprime(m)) ; fi ; end: a := proc(n) local m ; if n = 0 then RETURN(2); else for m from 0 do if A051700(m) = 3 * n then RETURN(m) ; fi ; od: fi ; end: seq(a(n), n=0..18);


CROSSREFS

Cf. A132470, A051700.
Sequence in context: A084298 A001772 A199206 * A210848 A247957 A152997
Adjacent sequences: A132858 A132859 A132860 * A132862 A132863 A132864


KEYWORD

more,nonn


AUTHOR

R. J. Mathar, Nov 18 2007


EXTENSIONS

7 more terms from R. J. Mathar, Jul 22 2009


STATUS

approved



