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A095293 Number of A095283-primes in range ]2^n,2^(n+1)]. 2
0, 2, 1, 4, 4, 9, 14, 29, 52, 90, 167, 312, 577, 1072, 2026, 3776, 7177, 13585, 25726, 49125, 93569, 178735, 342381, 657180, 1262818, 2430501, 4684999, 9040931, 17470670, 33798206, 65455531, 126889351, 246216909 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

As expected, the ratio a(n)/A095292(n) seems to approach 2: 0, 0, 1, 4, 1.33333, 2.25, 1.55556, 2.07143, 2.26087, 1.91489, 1.89773, 2.05263, 1.95593, 1.98519, 2.01793, 1.95344, 2.00924, 1.99633, 1.99287, 2.0083, 2.00075, 1.99746, 1.99841, 1.99971, 2.00034, 2.00001, 2.00018, 1.99977, 1.99971, 1.99997, 2.00004, 1.99995, 2.00003

LINKS

Table of n, a(n) for n=1..33.

A. Karttunen and J. Moyer: C-program for computing the initial terms of this sequence

Index entries for sequences related to occurrences of various subsets of primes in range 2^n,2^(n+1)

PROG

(PARI) a(n)=my(s); forprime(p=2^n+1, 2^(n+1), s+=valuation(p+1, 2)%2); s \\ Charles R Greathouse IV, Oct 09 2013

CROSSREFS

a(n) = A036378(n)-A095292(n). Cf. A095005.

Sequence in context: A008346 A119282 A241513 * A034409 A209478 A211178

Adjacent sequences:  A095290 A095291 A095292 * A095294 A095295 A095296

KEYWORD

nonn

AUTHOR

Antti Karttunen, Jun 04 2004

STATUS

approved

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Last modified September 20 13:45 EDT 2020. Contains 337264 sequences. (Running on oeis4.)