A049716 - OEIS

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A049716

a(n) = 2*n + 1 - prevprime(2*n + 1).

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

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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 ...