

A128193


First differences of values of n for Cullen primes in A005849.


1



140, 4572, 1082, 816, 11885, 13796, 177, 27187, 31169, 171594, 98856, 120624, 872929, 4973720, 351333
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OFFSET

1,1


COMMENTS

Carlos Rivera's Problem 50 is devoted to this topic. If we pair differences according to magnitude, we first obtain 177140=37 a prime. This raises the question as to whether there are other such prime values.


LINKS

Table of n, a(n) for n=1..15.
Carlos Rivera, Problem 50. Is there a Cullen prime Cn with n prime ?, The Prime Puzzles and Problems Connection.


FORMULA

a(n) = A005849(n+1)  A005849(n).  Michel Marcus, Sep 27 2020


EXAMPLE

a(1)=140 because the first pair of n are 1 and 141. 1411=140.


CROSSREFS

Cf. A005849, A128194.
Sequence in context: A255775 A199831 A264310 * A061607 A223349 A282613
Adjacent sequences: A128190 A128191 A128192 * A128194 A128195 A128196


KEYWORD

easy,nonn,more


AUTHOR

Enoch Haga, Feb 18 2007


EXTENSIONS

Offset 1 from Michel Marcus, Sep 27 2020
a(14)a(15) added by Florian Baur, Sep 27 2020


STATUS

approved



