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%I #19 May 25 2022 09:45:23
%S 1,1,14,148,14804,1480398,148039049,14803895356,1480389427723,
%T 148038942652481,14803894265116205,1480389426511476635,
%U 148038942651147507639,14803894265114750596056,1480389426511475059425814,148038942651147505942389607,14803894265114750594238756940
%N a(n) = floor(X/Y), where X = concatenation of cubes and Y = concatenation of natural numbers.
%C a(n) -> 148038942651147505942387547594667814093751032610233441970375...
%e a(6) = floor(182764125216/123456) = floor(1480398.888802...) = 1480398.
%p a:= n-> floor(parse(cat(i^3$i=1..n))/parse(cat($1..n))):
%p seq(a(n), n=1..17); # _Alois P. Heinz_, May 25 2022
%t f[n_] := (k = 1; x = y = "0"; While[k < n + 1, x = StringJoin[x, ToString[k^3]]; y = StringJoin[y, ToString[k]]; k++ ]; Return[ Floor[ ToExpression[x] / ToExpression[y]]] ); Table[ f[n], {n, 1, 20} ]
%t nn=20;With[{c=Table[IntegerDigits[n^3],{n,nn}],s=Table[IntegerDigits[n],{n,nn}]}, Table[Floor[FromDigits[Flatten[Take[c,i]]]/FromDigits[Flatten[Take[s,i]]]],{i,nn}]] (* _Harvey P. Dale_, Feb 10 2013 *)
%o (PARI) c1(n) = my(s=""); for(k=1, n, s=Str(s, k)); eval(s); \\ A007908
%o c3(n) = my(s=""); for(k=1, n, s=Str(s, k^3)); eval(s); \\ A019522
%o a(n) = c3(n)\c1(n); \\ _Michel Marcus_, May 25 2022
%Y Cf. A000578, A007908, A019522.
%Y Cf. A067091, A067092, A067093, A067094, A067095, A067096, A067097, A067098, A067099, A067100, A067101, A067102.
%Y See also A066700.
%K nonn,base
%O 1,3
%A _Robert G. Wilson v_, Jan 09 2002
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