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A142339
Primes of the form (p(2*n)-p(n))/2, where p(n)=n-th prime.
0
2, 13, 17, 19, 67, 83, 197, 257, 311, 409, 419, 557, 571, 587, 659, 677, 677, 733, 773, 827, 853, 877, 881, 971, 983, 1087, 1123, 1171, 1171, 1229, 1259, 1279, 1283, 1367, 1423, 1429, 1499, 1543, 1657, 1733, 1741, 1759, 1759, 1777, 1871, 1871, 1877, 1907
OFFSET
1,1
EXAMPLE
If n=2, then (p(2*2)-p(2))/2=(7-3)/2=2=a(1).
If n=7, then (p(2*7)-p(7))/2=(43-17)/2=13=a(2).
If n=8, then (p(2*8)-p(8))/2=(53-19)/2=17=a(3).
If n=9, then (p(2*9)-p(9))/2=(61-23)/2=19=a(4).
If n=24, then (p(2*24)-p(24))/2=(223-89)/2=67=a(5), etc.
CROSSREFS
Cf. A000040.
Sequence in context: A124277 A038889 A152652 * A348633 A105913 A020480
KEYWORD
nonn
AUTHOR
EXTENSIONS
739 replaced by 733, 983 added, 1759 duplicated etc. by R. J. Mathar, Oct 04 2008
STATUS
approved