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A213738 a(n) is the smallest prime of the form  n*m^q + 1 where m is an integer and q >= 2. 2
5, 17, 13, 17, 41, 97, 29, 73, 37, 41, 89, 97, 53, 113, 61, 257, 137, 73, 1217, 181, 337, 89, 829, 97, 101, 937, 109, 113, 233, 241, 1117, 257, 2113, 137, 281, 577, 149, 1217, 157, 641, 36901, 337, 173, 353, 181, 1151, 1693, 193, 197, 401, 409, 1301, 1697, 433 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Michel Lagneau, Table of n, a(n) for n = 1..10000

EXAMPLE

a(11) = 89 = 11*2^3 + 1.

MAPLE

with(numtheory):isA:= proc(n) local e ; e := seq(op(2, p), p=ifactors(n)[2]) ; return ( igcd(e) >=2 ) ; end proc:

A:= proc(n) option remember; local a; if n = 1 then 1; else for a from procname(n-1)+1 do if isA(a) then return a ; end if; end do; end if; end proc:

seq(A(n), n=1..100) ;

for m from 1 to 100 do:ii:=0:for q from 1 to 100 while(ii=0) do:n1:=A(q):p:=m*n1+1:if type(p, prime)=true and n1>1 then ii:=1: printf(`%d, `, p):else fi:od:od:

CROSSREFS

Cf. A001597, A213740.

Sequence in context: A180024 A178197 A070848 * A060829 A096896 A056850

Adjacent sequences:  A213735 A213736 A213737 * A213739 A213740 A213741

KEYWORD

nonn

AUTHOR

Michel Lagneau, Jun 19 2012

STATUS

approved

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Last modified December 10 03:42 EST 2016. Contains 278993 sequences.