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%I #16 Aug 31 2024 08:32:06
%S 1,5,31,247,529,559,1747,181,4651,147331,1276726,10379813,10527373,
%T 501426731,507546131,14874882499,120130384067,8121140473289,
%U 597694372183697,7829048769596861,7886595152525441,341425446875737163,26430832817384951,2579018441538210647,137426518826740878691
%N a(n) = numerator of Sum_{i=1..n} 1/A031216(i).
%H Alois P. Heinz, <a href="/A375525/b375525.txt">Table of n, a(n) for n = 1..882</a>
%e The first few fractions are 1/2, 5/6, 31/30, 247/210, 529/420, 559/420, 1747/1260, 181/126, 4651/3150, 147331/97650, 1276726/830025, 10379813/6640200, 10527373/6640200, ...
%p b:= n-> (l-> add(l[i]*11^(i-1), i=1..nops(l)))(convert(ithprime(n),base,10)):
%p g:= proc(n) option remember; `if`(n<1, 0, g(n-1)+1/b(n)) end:
%p a:= n-> numer(g(n)):
%p seq(a(n), n=1..25); # _Alois P. Heinz_, Aug 30 2024
%o (PARI) a(n) = numerator(sum(i=1, n, 1/fromdigits(digits(prime(i)), 11))); \\ _Michel Marcus_, Aug 31 2024
%Y Cf. A031216, A375526.
%K nonn,frac,new
%O 1,2
%A _N. J. A. Sloane_, Aug 30 2024.
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