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%I #9 Sep 21 2023 18:37:22
%S 1,2,3,6,7,15,20,26,29,30,35,40,42,43,46,52,57,61,65,70,75,84,92,99,
%T 100,102,105,125,139,140,144,149,154,164,171,179,183,197,202,214,218,
%U 223,227,232,234,245,247,251,258,265,272,280,288,290,294,299,304,323,325
%N Numbers n such that the n-th prime + n-th nonprime is itself prime.
%H Harvey P. Dale, <a href="/A125167/b125167.txt">Table of n, a(n) for n = 1..1000</a>
%e The 15th prime is 47, while the 15th nonprime is 24. 47+24=71 which is itself prime. Similarly, the 30th prime is 113, while the 30th nonprime is 44. 113+44=157 which is prime.
%t Module[{nn=500,np,tbl},np=Select[Range[nn],!PrimeQ[#]&];tbl=Table[{n,np[[n]]+Prime[n]},{n,Length[ np]}];Select[tbl,PrimeQ[#[[2]]]&]][[;;,1]] (* _Harvey P. Dale_, Sep 21 2023 *)
%Y Cf. A000040, A018252, A022797.
%K easy,nonn
%O 1,2
%A _Jason G. Wurtzel_, Nov 22 2006
%E More terms from _Klaus Brockhaus_, Nov 23 2006
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