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A139231
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First differences of Mersenne primes A000668.
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11
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4, 24, 96, 8064, 122880, 393216, 2146959360, 2305843007066210304, 618970017336847128235868160, 162258657859193720701440560726016, 170141021201192402518323912137873817600
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OFFSET
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1,1
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LINKS
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Table of n, a(n) for n=1..11.
Omar E. Pol, Determinacion geometrica de los numeros primos y perfectos".
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FORMULA
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a(n) = A000668(n+1) - A000668(n).
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EXAMPLE
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a(1)=4 because A000668(1)=3 and A000668(2)=7 then 7-3 = 4.
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MATHEMATICA
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A000668 := Select[2^Range[1000] - 1, PrimeQ]; Table[A000668[[n + 1]] - A000668[[n]], {n, 1, 10}] (* G. C. Greubel, Oct 03 2017 *)
Differences[2^MersennePrimeExponent[Range[20]]-1] (* Harvey P. Dale, Mar 31 2022 *)
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PROG
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(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
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CROSSREFS
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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
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KEYWORD
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nonn
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AUTHOR
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Omar E. Pol, Apr 18 2008
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EXTENSIONS
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a(8)-a(11) from Felix Fröhlich, Aug 12 2014
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STATUS
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approved
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