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A175148 a(n) = number of primes p, p <= 2^n, where 2^n + p is composite. 1
0, 1, 1, 2, 3, 8, 13, 22, 43, 79, 140, 258, 480, 877, 1646, 3083, 5788, 10940, 20623, 39191, 74441, 141826, 270992, 518323, 993869, 1910174, 3674150, 7078905, 13654626, 26375091, 51007193, 98748888, 191381911 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

COMMENTS

Terms through a(18) calculated by M. F. Hasler.

LINKS

Table of n, a(n) for n=0..32.

FORMULA

a(n) = A007053(n) - A175147(n).

CROSSREFS

Cf. A007053, A175147.

Sequence in context: A102315 A142880 A147329 * A147417 A147357 A004138

Adjacent sequences:  A175145 A175146 A175147 * A175149 A175150 A175151

KEYWORD

more,nonn

AUTHOR

Leroy Quet, Feb 24 2010

EXTENSIONS

a(19)-a(32) from Ray Chandler, Mar 05 2010

STATUS

approved

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Last modified November 18 02:54 EST 2017. Contains 294840 sequences.