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%I #12 Apr 19 2024 03:16:19
%S 1,2,4,6,8,10,13,19,23,25,29,33,35,39,47,51,55,59,63,71,75,77,83,95,
%T 99,105,117,121,126,131,136,146,150,154,170,178,180,184,196,202,207,
%U 212,216,232,240,242,251,269,277,285,293,297,303,315,327,339,343,345,355,365
%N a(n) = Sum_{i=1..n} u_3(i)*u_3(i+1), where u_3(n) = A034836(n).
%C For background references see A330570.
%H Amiram Eldar, <a href="/A331130/b331130.txt">Table of n, a(n) for n = 1..10000</a>
%t s[1] = 1; s[n_] := Module[{e = FactorInteger[n][[;; , 2]]}, If[IntegerQ[Surd[n, 3]], 1/3, 0] + (Times @@ ((e + 1)*(e + 2)/2))/6 + (Times @@ (Floor[e/2] + 1))/2]; With[{t = Array[s, 100]}, Accumulate[Most[t] * Rest[t]]] (* _Amiram Eldar_, Apr 19 2024 *)
%Y Cf. A034836, A331080.
%K nonn
%O 1,2
%A _N. J. A. Sloane_, Jan 10 2020
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