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a(n) = floor(m), where li(m) = n and li is the logarithmic integral. We consider only real and positive m.
0

%I #26 Oct 08 2022 10:12:48

%S 1,2,4,5,7,9,11,14,17,20,23,26,29,33,36,40,44,48,52,56,60,64,68,72,77,

%T 81,85,90,94,99,104,108,113,118,122,127,132,137,142,147,152,157,162,

%U 167,172,178,183,188,193,198,204,209,214,220,225,231,236,242,247,253,258

%N a(n) = floor(m), where li(m) = n and li is the logarithmic integral. We consider only real and positive m.

%C We use for li(x) and x > 1 the Cauchy principal value of Integral_{0..x} dt/log(t). This is stated to prevent confusion with Li(x), which is often defined so that Li(x) = li(x) - li(2).

%Y Cf. A052435, A089963, A096353, A223853, A337734, A337735.

%K nonn

%O 1,2

%A _Thomas Scheuerle_, Jul 25 2022