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%I #13 Aug 30 2024 20:44:11
%S 1,3,11,25,137,49,363,761,7129,80939,83249,1109957,1135697,1159721,
%T 2364487,40916999,13865893,267536047,271415923,274943083,6401288429,
%U 6475652719,32735212187,33078431987,300680459483,43364113769,1269032646901,1280123549581,40016557117411,3666283538201
%N a(n) = numerator of Sum_{i=1..n} 1/A171397(i).
%C Suggested by A375805.
%H Alois P. Heinz, <a href="/A375523/b375523.txt">Table of n, a(n) for n = 1..2082</a>
%e The first few sums are 1, 3/2, 11/6, 25/12, 137/60, 49/20, 363/140, 761/280, 7129/2520, 80939/27720, 83249/27720, 1109957/360360, 1135697/360360, 1159721/360360, 2364487/720720, ...
%p b:= n-> (l-> add(l[i]*11^(i-1), i=1..nops(l)))(convert(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..30); # _Alois P. Heinz_, Aug 30 2024
%Y Cf. A171397, A375805, A375524, A001008/A002805.
%K nonn,frac
%O 1,2
%A _N. J. A. Sloane_, Aug 30 2024