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%I #7 Jan 06 2021 00:42:20
%S 0,1,2,3,4,6,7,8,9,10,11,12,13,14,15,16,17,19,20,21,22,23,24,25,26,27,
%T 28,29,30,32,33,34,35,36,37,38,39,41,42,43,44,45,46,47,48,49,50,51,52,
%U 53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,70,71,72,73,74,75,76
%N a(n) = Sum_{k=1..n} floor(floor((n-k)^(1/k))/k).
%t Table[Sum[Floor[Floor[(n - k)^(1/k)]/k], {k, n}], {n, 100}]
%o (PARI) a(n) = sum(k=1, n, sqrtnint(n-k, k)\k); \\ _Michel Marcus_, Jan 03 2021
%Y Cf. A340289.
%K nonn
%O 1,3
%A _Wesley Ivan Hurt_, Jan 03 2021