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A174215 First differences of A174214. 3
2, 1, 1, 1, 1, 6, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 13, 1, 1, 1, 5, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 31, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

9,1

COMMENTS

If a(n) is odd, then it is 1 or prime; if a(n) is even, then 2+a(n)/2 is prime.

LINKS

Table of n, a(n) for n=9..120.

V. Shevelev, Theorems on twin primes-dual case, arXiv:0912.4006

FORMULA

a(n) = A174214(n+1)-A174214(n).

CROSSREFS

Cf. A167495, A166945, A174214

Sequence in context: A124341 A275062 A247005 * A305567 A134744 A260875

Adjacent sequences:  A174212 A174213 A174214 * A174216 A174217 A174218

KEYWORD

nonn,easy

AUTHOR

Vladimir Shevelev, Mar 12 2010

EXTENSIONS

Terms corrected, using the Mathar-Layman corrections of A174214, by Vladimir Shevelev, Mar 26 2010

STATUS

approved

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Last modified October 19 02:41 EDT 2019. Contains 328211 sequences. (Running on oeis4.)