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A254429
a(0) = 0; for n >= 0, a(n+1) = 2^a(n) + 1.
2
0, 2, 5, 33, 8589934593
OFFSET
0,2
FORMULA
a(n+1) = A000051(a(n)). - Reinhard Zumkeller, Jan 31 2015
MATHEMATICA
RecurrenceTable[{a[0]==0, a[n]==2^a[n-1] + 1}, a, {n, 5}] (* Vincenzo Librandi, Feb 01 2015 *)
NestList[2^#+1&, 0, 4] (* Harvey P. Dale, Mar 26 2023 *)
PROG
(Haskell)
a254429 n = a254429_list !! n
a254429_list = iterate ((+ 1) . (2 ^)) 0
-- Reinhard Zumkeller, Jan 31 2015
(Magma) [n le 2 select 2*(n-1) else 2^Self(n-1)+1: n in [1..5]]; // Vincenzo Librandi, Feb 01 2015
CROSSREFS
Cf. A000051.
Sequence in context: A208985 A333738 A114793 * A298945 A027303 A357446
KEYWORD
nonn
AUTHOR
Max Alekseyev, Jan 30 2015
STATUS
approved