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A128194 Absolute value of second differences of values of n for Cullen primes in A005849. 1
4432, 3490, 266, 11069, 1911, 13619, 27010, 3982, 31169, 72698, 21768, 752305 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

In this sequence a(3) and a(5) are primes. Also a(1)+1, a(6)+1 and a(7)+1 are primes. And a(10)-1 is prime. These may at some future time begin three new sequences.

LINKS

Table of n, a(n) for n=0..11.

FORMULA

Find the absolute value of second differences of overlapping pairs of values of n

EXAMPLE

a(0)=4432 because the first two values of first differences in A128193 are 140 and 4572. 4572-140=4432, the first second difference.

CROSSREFS

Cf. A005849 A128193.

Sequence in context: A108008 A275773 A060363 * A184091 A309487 A206016

Adjacent sequences:  A128191 A128192 A128193 * A128195 A128196 A128197

KEYWORD

easy,nonn

AUTHOR

Enoch Haga, Feb 18 2007

STATUS

approved

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Last modified May 9 07:36 EDT 2021. Contains 343692 sequences. (Running on oeis4.)