OFFSET
1,2
COMMENTS
This sequence is infinite if the generalized Dickson's conjecture holds.
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
Wikipedia, Bunyakovsky conjecture
Wikipedia, Dickson's conjecture
EXAMPLE
. | (i, j, k) such that | corresponding
. | a(n) = A005574(i) | prime triples
. | | = A087370(j) | let m = a(n):
. n | a(n) | = A056561(k) | (m^2+1, 3*m-1, m^2+m+41)
. ---+------+---------------------+--------------------------
. 1 | 1 | (1, 1, 2) | (2, 2, 43)
. 2 | 2 | (2, 2, 3) | (5, 5, 47)
. 3 | 4 | (3, 3, 5) | (17, 11, 61)
. 4 | 6 | (4, 4, 7) | (37, 17, 83)
. 5 | 10 | (5, 6, 11) | (101, 29, 151)
. 6 | 14 | (6, 7, 13) | (197, 41, 251)
. 7 | 16 | (7, 8, 15) | (257, 47, 313)
. 8 | 20 | (8, 10, 21) | (401, 59, 461)
. 9 | 24 | (9, 11, 25) | (597, 71, 641)
. 10 | 36 | (11, 15, 37) | (1297, 107, 1373)
. 11 | 66 | (15, 24, 61) | (4357, 197, 4463)
. 12 | 90 | (18, 31, 79) | (8101, 269, 8231) .
PROG
(Haskell)
import Data.List.Ordered (isect)
a259645 n = a259645_list !! (n-1)
a259645_list = a005574_list `isect` a087370_list `isect` a056561_list
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Jul 03 2015
STATUS
approved