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 A049716 a(n) = 2*n + 1 - prevprime(2*n + 1). 5
 1, 2, 2, 2, 4, 2, 2, 4, 2, 2, 4, 2, 4, 6, 2, 2, 4, 6, 2, 4, 2, 2, 4, 2, 4, 6, 2, 4, 6, 2, 2, 4, 6, 2, 4, 2, 2, 4, 6, 2, 4, 2, 4, 6, 2, 4, 6, 8, 2, 4, 2, 2, 4, 2, 2, 4, 2, 4, 6, 8, 10, 12, 14, 2, 4, 2, 4, 6, 2, 2, 4, 6, 8, 10, 2, 2, 4, 6, 2, 4, 6, 2, 4, 2, 4, 6, 2, 4, 6, 2, 2, 4 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Robert Israel, Table of n, a(n) for n = 1..10000 FORMULA a(n) = A049711(2*n+1). - R. J. Mathar, Oct 26 2015 EXAMPLE n: 1 2 3 4 5 6 7 8 ... 2n+1: 3 5 7 9 11 13 15 17 ... pp: 2 3 5 7 7 11 13 13 ... diff: 1 2 2 2 4 2 2 4 ... MAPLE seq(2*n+1-prevprime(2*n+1), n=1..100); # Robert Israel, Jul 05 2018 MATHEMATICA Table[2n+1-NextPrime[2n+1, -1], {n, 100}] (* Harvey P. Dale, Sep 21 2013 *) PROG (PARI) a(n) = 2*n+1-precprime(2*n); \\ Michel Marcus, Jul 06 2018 CROSSREFS Cf. A049613, A049653, A049711, A049847. Sequence in context: A102430 A160691 A367626 * A361289 A188903 A366534 Adjacent sequences: A049713 A049714 A049715 * A049717 A049718 A049719 KEYWORD nonn AUTHOR N. J. A. Sloane STATUS approved

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Last modified May 30 14:34 EDT 2024. Contains 372968 sequences. (Running on oeis4.)