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A016104 2^2^2^ ... 2^w (with n 2's), where w = 1.9287800..... 0
1, 3, 13, 16381 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

w is uniquely defined as the largest value such that for all n>0, a(n) is prime. - Charles R Greathouse IV Oct 25 2006

Hardy's paper uses this as an example, although the sequence is not well-defined there. The next term is probably 2^16382-35411, a 4932-digit prp. - Charles R Greathouse IV Oct 25 2006

REFERENCES

P. Ribenboim, Prime number records, Two-Year College Math. Jnl., 25 (1994), pp. 280-290.

E. M. Wright, A prime-representing function, American Mathematical Monthly, 58 (1951), pp. 616-618.

FORMULA

a(0) = 1, a(n) = the greatest prime less than 2^(a(n-1)+1). - Charles R Greathouse IV Oct 25 2006

CROSSREFS

Cf. A086238.

Sequence in context: A108583 A127855 A087333 * A112856 A007523 A092830

Adjacent sequences:  A016101 A016102 A016103 * A016105 A016106 A016107

KEYWORD

nonn

AUTHOR

Robert G. Wilson v (rgwv(AT)rgwv.com)

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Last modified February 14 14:07 EST 2012. Contains 205623 sequences.