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A261140 a(n) = 3486107472997423 + (n-1)*371891575525470. 6
3486107472997423, 3857999048522893, 4229890624048363, 4601782199573833, 4973673775099303, 5345565350624773, 5717456926150243, 6089348501675713, 6461240077201183, 6833131652726653, 7205023228252123, 7576914803777593, 7948806379303063, 8320697954828533 (list; graph; refs; listen; history; text; internal format)
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.

LINKS

Colin Barker, Table of n, a(n) for n = 1..1000

Jens Kruse Andersen, All known AP24 to AP26.

Wikipedia, Largest known primes in AP.

Index entries for linear recurrences with constant coefficients, signature (2,-1).

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}]

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

CROSSREFS

Cf. A002110, A204189, A260751.

Sequence in context: A008913 A335395 A064585 * A116500 A173533 A260751

Adjacent sequences:  A261137 A261138 A261139 * A261141 A261142 A261143

KEYWORD

nonn,easy

AUTHOR

Marco Ripà, Aug 10 2015

STATUS

approved

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Last modified April 20 00:33 EDT 2021. Contains 343117 sequences. (Running on oeis4.)