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A261140
a(n) = 3486107472997423 + (n-1)*371891575525470.
12
3486107472997423, 3857999048522893, 4229890624048363, 4601782199573833, 4973673775099303, 5345565350624773, 5717456926150243, 6089348501675713, 6461240077201183, 6833131652726653, 7205023228252123, 7576914803777593, 7948806379303063, 8320697954828533
OFFSET
1,1
COMMENTS
The terms n = 1..26 are prime. This is the longest sequence of primes in arithmetic progression with smallest end, a(26)=12783396861134173, known as of August 10, 2015.
FORMULA
a(n) = 3486107472997423 + (n-1)*1666981*A002110(9).
G.f.: -x*(3114215897471953*x-3486107472997423) / (x-1)^2. - Colin Barker, Aug 25 2015
EXAMPLE
a(26) = 3486107472997423 + 25*371891575525470 = 12783396861134173 is prime.
MATHEMATICA
Table[3486107472997423 + (n - 1) 371891575525470, {n, 1, 20}]
LinearRecurrence[{2, -1}, {3486107472997423, 3857999048522893}, 20] (* Harvey P. Dale, May 14 2022 *)
PROG
(Magma) [3486107472997423+(n-1)*371891575525470: n in [1..20]];
(PARI) Vec(-x*(3114215897471953*x-3486107472997423)/(x-1)^2 + O(x^40)) \\ Colin Barker, Aug 25 2015
KEYWORD
nonn,easy
AUTHOR
Marco Ripà, Aug 10 2015
STATUS
approved