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A139240
First differences of Mersenne numbers A001348, divided by 4.
5
1, 6, 24, 480, 1536, 30720, 98304, 1966080, 132120576, 402653184, 33822867456, 515396075520, 1649267441664, 32985348833280, 2216615441596416, 141863388262170624, 432345564227567616, 36317027395115679744, 553402322211286548480, 1770887431076116955136, 148754544210393824231424
OFFSET
1,2
LINKS
FORMULA
a(n) = A139238(n)/4 = A139239(n)/2.
MATHEMATICA
Differences[2^Prime[Range[25]]-1]/4 (* Paolo Xausa, Oct 20 2023 *)
PROG
(PARI) a(n)=my(p=prime(n)); (2^nextprime(p+1)-2^p)/4 \\ Charles R Greathouse IV, Jan 03 2013
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Omar E. Pol, Apr 19 2008
EXTENSIONS
a(10)-a(21) from Paolo Xausa, Oct 20 2023
STATUS
approved