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A294154
Base-2 logarithm of product of primes between 2^n+1 and 2^(n+1).
0
1, 1, 5, 7, 22, 39, 84, 173, 367, 716, 1444, 2945, 5823, 11817, 23457, 47117, 94496, 188670, 378296, 755437, 1512435, 3024742, 6049260, 12099777, 24205776, 48402649, 96809896, 193632363, 387252738, 774544273, 1549044943
OFFSET
0,3
COMMENTS
Inspired by Bertrand's postulate and complexity of algorithms using Farey fraction sets of size 2^n.
The log of this sequence seems linear after a few terms.
MATHEMATICA
Table[Floor[
Log[2, Times @@
Table[Prime[i], {i, PrimePi[2^(n)] + 1,
PrimePi[2^(n + 1)]}]]], {n, 0, 20}]
CROSSREFS
Cf. A036378 (number of primes between 2^n+1 and 2^(n+1).
Cf. A293696, A293697 (additive view of the primes between 2^n+1 and 2^(n+1).
Sequence in context: A350193 A248086 A076409 * A260658 A028281 A240102
KEYWORD
nonn,more
AUTHOR
Olivier Gérard, Oct 24 2017
EXTENSIONS
a(26)-a(30) from Robert Price, Nov 30 2017
STATUS
approved