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A139190
a(n) = (prime(n)!-2)/2.
18
0, 2, 59, 2519, 19958399, 3113510399, 177843714047999, 60822550204415999, 12926008369442488319999, 4420880996869850977271807999999, 4111419327088961408862781439999999, 6881876545613172523157989790790451199999999, 16726263306581903554085031026720375832575999999999, 30207631531686917818677566034256998753632255999999999, 129311620755584090321482177576805989984598816194559999999999, 2137441642030012782149006876694699824845171894183406862335999999999999
OFFSET
1,2
LINKS
FORMULA
a(n) = (A139189(n)-1)/2. - R. J. Mathar, May 25 2008
MATHEMATICA
Table[(Prime[n]! - 2)/2, {n, 1, 20}]
PROG
(PARI) a(n) = (prime(n)!-2)/2 \\ Charles R Greathouse IV, Apr 29 2015
KEYWORD
nonn
AUTHOR
Artur Jasinski, Apr 11 2008
EXTENSIONS
More terms from R. J. Mathar, May 25 2008
STATUS
approved