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A139231 First differences of Mersenne primes A000668. 11
4, 24, 96, 8064, 122880, 393216, 2146959360, 2305843007066210304, 618970017336847128235868160, 162258657859193720701440560726016, 170141021201192402518323912137873817600 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..11.

Omar E. Pol, Determinacion geometrica de los numeros primos y perfectos".

FORMULA

a(n) = A000668(n+1) - A000668(n).

EXAMPLE

a(1)=4 because A000668(1)=3 and A000668(2)=7 then 7-3 = 4.

MATHEMATICA

A000668 := Select[2^Range[1000] - 1, PrimeQ]; Table[A000668[[n + 1]] - A000668[[n]], {n, 1, 10}] (* G. C. Greubel, Oct 03 2017 *)

PROG

(PARI) a=0; b=0; forprime(p=1, 1e2, if(ispseudoprime(2^p-1) && a==0, a=2^p-1); if(ispseudoprime(2^p-1) && a!=0, b=2^p-1; if(a!=b, print1(b-a, ", ")); a=b)) \\ Felix Fröhlich, Aug 12 2014

CROSSREFS

Cf. A000668, A139228, A139229, A139230, A139232, A139233, A139234, A139235, A139236, A139237.

Sequence in context: A119920 A100738 A139238 * A052462 A260217 A048806

Adjacent sequences:  A139228 A139229 A139230 * A139232 A139233 A139234

KEYWORD

nonn

AUTHOR

Omar E. Pol, Apr 18 2008

EXTENSIONS

a(8)-a(11) from Felix Fröhlich, Aug 12 2014

STATUS

approved

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Last modified January 23 01:30 EST 2020. Contains 331166 sequences. (Running on oeis4.)