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A056821
Totient of the Woodall numbers (A003261), n*2^n -1.
2
1, 6, 22, 36, 104, 382, 712, 1936, 4320, 6824, 15012, 46992, 79344, 183000, 421008, 480000, 1453784, 4658784, 8877792, 20958480, 38887680, 61284600, 110250264, 388201176, 719023536, 1734432480, 2889658368, 4745378304, 10350643968, 32212254718, 66251144568
OFFSET
1,2
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..853 (terms 1..150 from Vincenzo Librandi)
FORMULA
a(n) = A000010(A003261(n)).
MAPLE
a:= n-> numtheory[phi](n*2^n-1):
seq(a(n), n=1..35); # Alois P. Heinz, Apr 15 2019
MATHEMATICA
Table[EulerPhi[n 2^n - 1], {n, 1, 35}]
PROG
(Magma) [EulerPhi(n*2^n-1): n in [1..30]]; // Vincenzo Librandi, Apr 15 2019
(PARI) a(n) = eulerphi(n*2^n -1); \\ Michel Marcus, Apr 15 2019
CROSSREFS
Sequence in context: A046408 A123017 A264043 * A031083 A218015 A031305
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Aug 31 2000
STATUS
approved