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%I #13 Jul 27 2021 06:22:15
%S 0,1,3,3,8,12,6,27,27,9,64,48,12,125,75,15,216,108,18,343,147,21,512,
%T 192,24,729,243,27,1000,300,30,1331,363,33,1728,432,36,2197,507,39,
%U 2744,588,42,3375,675,45,4096,768,48,4913,867,51,5832,972,54,6859,1083,57,8000,1200
%N Successive numbers arising from the Moessner construction of the cubes on page 64 of Conway-Guy's "Book of Numbers".
%C a(3*k+1) = (k+1)^3 for k >= 0.
%D J. H. Conway and R. K. Guy, The Book of Numbers, Copernicus Press, NY, 1996. Sequence can be seen in the successive circled numbers at the top of page 64.
%F a(n) = n if n mod 3 = 0, = ((n+2)/3)^3 if n mod 3 = 1, and otherwise (n+1)^2/3.
%p f:=proc(n) if (n mod 3) = 0 then n
%p elif (n mod 3) = 1 then ((n+2)/3)^3;
%p else (n+1)^2/3; fi; end;
%p [seq(f(n),n=0..100)];
%o (Python)
%o def A346005(n): return n if n % 3 == 0 else ((n+2)//3)**3 if n % 3 == 1 else (n+1)**2//3 # _Chai Wah Wu_, Jul 25 2021
%Y Cf. A125714, A346004, A346006-A346007, A346595.
%K nonn
%O 0,3
%A _N. J. A. Sloane_, Jul 25 2021