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A073847 a(0) = 1, c(0) = 1, a(n) for n > 0 is the smallest prime a(n-1) + c(n), where c(n) is composite and larger than c(n-1).

%I A073847 #7 Dec 05 2013 19:55:31
%S A073847 1,5,11,19,29,41,59,79,101,127,157,191,227,269,313,359,409,461,521,
%T A073847 587,659,733,809,887,967,1049,1151,1259,1373,1489,1607,1733,1861,1993,
%U A073847 2129,2267,2411,2557,2707,2861,3019,3181,3347,3517,3691,3877,4073,4271,4481
%N A073847 a(0) = 1, c(0) = 1, a(n) for n > 0 is the smallest prime a(n-1) + c(n), where c(n) is composite and larger than c(n-1).
%C A073847 Same as A070865 after first term. - _David Wasserman_, Jun 27 2005
%e A073847 a(6) = 59 since 59 = a(5) + c(6) = 41 + 18, 18 is composite and larger than c(5) = 12 and the composite numbers 14, 15, 16 do not lead to a prime when added to 41.
%t A073847 a[n_] := a[n] = NextPrim[a[n - 1] + a[n - 1] - a[n - 2]]; a[0] = 1; a[1] = 5; Table[ a[n], {n, 0, 50}]
%o A073847 (PARI) {print1(a=1,","); c=1; for(n=1,48,c++; while(isprime(c)||!isprime(a+c),c++); a=a+c; print1(a,","))}
%K A073847 nonn
%O A073847 0,2
%A A073847 _Amarnath Murthy_, Aug 14 2002
%E A073847 Edited and extended by _Klaus Brockhaus_ and _Robert G. Wilson v_, Aug 14 2002