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A242083 3^p - 2^p - 1, where p is prime. 2
4, 18, 210, 2058, 175098, 1586130, 129009090, 1161737178, 94134790218, 68629840493970, 617671248800298, 450283768452043890, 36472994178147530850, 328256958598444055418, 26588814218220014932458, 19383245658672820642055730 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

For p>3, all terms are divisible by 42.

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..320

FORMULA

a(n) = abs(A083321(A000040(n)). - Michel Marcus, May 05 2014

MATHEMATICA

Table[(3^Prime[n] - 2^Prime[n] - 1), {n, 1, 30}]

3^#-2^#-1&/@Prime[Range[20]] (* Harvey P. Dale, Aug 05 2016 *)

PROG

(MAGMA) [3^p-2^p-1: p in PrimesUpTo(60)]

(PARI) a(n) = my(p = prime(n)); 3^p-2^p-1; \\ Michel Marcus, May 05 2014

(Sage) print [3^p-2^p-1 for p in primes(60)] # Bruno Berselli, May 12 2014

CROSSREFS

Cf. A083321, A204768.

Sequence in context: A201346 A174663 A197786 * A327335 A275965 A071173

Adjacent sequences:  A242080 A242081 A242082 * A242084 A242085 A242086

KEYWORD

nonn

AUTHOR

Vincenzo Librandi, May 04 2014

STATUS

approved

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Last modified October 16 06:05 EDT 2019. Contains 328046 sequences. (Running on oeis4.)