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%I #10 May 13 2017 00:08:26
%S 1,2,3,4,7,10,13,24,43,46,51,56,75,76,91,102,109,132,145,166,171,176,
%T 177,196,201,208,211,228,239,248,255,286,291,296,303,314,327,346,393,
%U 430,433,454,457,480,503,506,527,534,557,594,619,630,659,708,719,728
%N Starting from a(1)=1, a(n) is the minimum integer greater than a(n-1) such that a(n)+a(n-1) and a(n)*a(n-1)+1 are both primes.
%C Terms are alternately odd and even.
%H Paolo P. Lava, <a href="/A228588/b228588.txt">Table of n, a(n) for n = 1..1000</a>
%e a(9)=43 and 43+44=87, 43+45=88 are not primes but 43+46=89 is prime and also 43*46+1=1979. Thus a(10)=51.
%p with(numtheory); P:=proc(q) local a, b, n; a:=1; b:=0; print(a);
%p for n from 1 to q do while not isprime(a+b) and not isprime (a*b+1) do
%p b:=b+2; od; print(b); a:=b; b:=b+1; od; print(); end: P(10^4);
%Y Cf. A228589, A228590.
%K nonn
%O 1,2
%A _Paolo P. Lava_, Aug 27 2013
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