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%I #28 Sep 08 2022 08:44:32
%S 3,7,14,23,36,49,66,83,104,129,152,181,210,239,272,309,348,385,428,
%T 471,514,563,612,665,722,777,832,891,950,1013,1088,1155,1226,1295,
%U 1374,1447,1526,1607,1688,1773,1860,1945,2040,2129,2222,2315,2420,2527,2628,2729
%N a(n) = n^2 + prime(n).
%C Sum of reciprocals = 0.766167481.... - _Cino Hilliard_, Dec 31 2003
%C The subset of primes begins: 3, 7, 23, 83, 181, 239, 563, 1013, 1447, 1607, 2129, 2729 = A184935. The subset of squares begins: 36, 49, no more through n = 100. - _Jonathan Vos Post_, Feb 02 2011
%C No more squares using primes < 10^10 (n ~ 45 million). The naive heuristic (not really applicable here, but it's a starting point) suggests something like sqrt(log(x)) up to x. - _Charles R Greathouse IV_, Feb 06 2011
%t Table[n^2+Prime[n],{n,50}] (* _Harvey P. Dale_, Feb 28 2015 *)
%o (PARI) primeppwr(n) = sr=0; for(x=1,n, y=x^2+prime(x); print1(y","); sr+=1./y; ); print(); print(sr) \\ _Cino Hilliard_
%o (Magma) [n^2 +NthPrime(n): n in [1..250]]; // _Vincenzo Librandi_, Apr 14 2011
%Y Cf. A184935.
%K nonn,easy
%O 1,1
%A wild(AT)edumath.u-strasbg.fr (Daniel Wild)
%E More terms from _Cino Hilliard_, Dec 31 2003
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