login
A098389
Prime(n) - floor(log_2(prime(n))).
5
1, 2, 3, 5, 8, 10, 13, 15, 19, 25, 27, 32, 36, 38, 42, 48, 54, 56, 61, 65, 67, 73, 77, 83, 91, 95, 97, 101, 103, 107, 121, 124, 130, 132, 142, 144, 150, 156, 160, 166, 172, 174, 184, 186, 190, 192, 204, 216, 220, 222, 226, 232, 234, 244, 249, 255, 261, 263, 269, 273
OFFSET
1,2
COMMENTS
a(n) = A000040(n) - A098388(n).
EXAMPLE
a(10) = A000040(10) - A098388(10) = 29 - 4 = 25.
MATHEMATICA
#-Floor[Log[2, #]]&/@Prime[Range[60]] (* Harvey P. Dale, Nov 06 2011 *)
PROG
(PARI) a(n)=my(p=prime(n)); p-log(p+.5)\log(2) \\ Charles R Greathouse IV, May 29 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Sep 06 2004
STATUS
approved