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A073627 a(1)=a(2)=1; for n > 2, a(n) is the smallest integer such that a(n) > a(n-1) and a(n)+a(n-1) is prime.

%I A073627 #18 Jan 18 2017 23:05:20
%S A073627 1,1,2,3,4,7,10,13,16,21,22,25,28,31,36,37,42,47,50,51,52,55,58,69,70,
%T A073627 79,84,89,90,91,100,111,112,115,118,121,130,133,136,141,142,151,156,
%U A073627 157,160,171,176,177,182,185,188,191,192,197,200,201,208,211,220,223
%N A073627 a(1)=a(2)=1; for n > 2, a(n) is the smallest integer such that a(n) > a(n-1) and a(n)+a(n-1) is prime.
%C A073627 Essentially the same as A062042. [_John W. Layman_, Oct 11 2013]
%H A073627 T. D. Noe, <a href="/A073627/b073627.txt">Table of n, a(n) for n = 1..1000</a>
%t A073627 s=1; Join[{1,1}, Table[k=s+1; While[ !PrimeQ[k+s], k++ ]; s=k, {100}]] (* _T. D. Noe_, Nov 02 2009 *)
%o A073627 (PARI) FirstTerms(n)={my(x=1,y,a=vector(n),j=2);a[1]=1;a[2]=1;while(j++<=n,y=x+1;while(!isprime(x+y),y++);x=y;a[j]=y);return(a)} \\ _R. J. Cano_, Jan 18 2017
%Y A073627 Cf. A073628.
%K A073627 nonn
%O A073627 1,3
%A A073627 _Amarnath Murthy_, Aug 08 2002
%E A073627 Edited by _Matthew Conroy_, Oct 21 2002
%E A073627 Definition corrected by _T. D. Noe_, Nov 02 2009