A060271 - OEIS

A060271

Difference between smallest prime following and largest prime preceding 2*(n-th prime).

2, 4, 4, 4, 6, 6, 4, 4, 6, 6, 6, 4, 6, 8, 4, 14, 14, 6, 10, 10, 6, 4, 6, 4, 12, 12, 12, 12, 4, 6, 6, 6, 4, 14, 14, 4, 14, 6, 10, 6, 8, 4, 6, 8, 4, 10, 6, 8, 4, 4, 12, 8, 4, 12, 18, 18, 6, 10, 6, 6, 10, 4, 12, 12, 10, 12, 4, 10, 10, 8, 10, 6, 8, 4, 8, 14, 10, 12, 10, 10, 14, 4, 14, 4, 4, 20, 8

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OFFSET

2,1

LINKS

Table of n, a(n) for n=2..88.

EXAMPLE

n=1: p(1)=2, 2p(1)=4 is between 3 and 5, their difference is 2=a(1); n=6: p(6)=13, 2p(6)=26 is between 23 and 29 and their difference is 6=a(6).

MAPLE

with(numtheory): [seq(nextprime(2*ithprime(j))-prevprime(2*ithprime(j)), j=2...256)];

MATHEMATICA

dsplp[n_]:=Module[{np=2Prime[n]}, NextPrime[np]-NextPrime[np, -1]]; Array[ dsplp, 90, 2] (* Harvey P. Dale, Mar 20 2013 *)

CROSSREFS