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Difference between the closest square and the closest cube to n.
5

%I #20 Jul 02 2018 01:43:04

%S 0,0,0,3,3,4,4,1,1,1,1,1,1,8,8,8,8,8,11,11,11,2,2,2,2,2,2,2,2,2,2,9,9,

%T 9,9,9,9,9,9,9,9,9,9,22,22,22,15,15,15,15,15,15,15,15,15,15,15,0,0,0,

%U 0,0,0,0,0,0,0,0,0,0,0,0,0,17,17,17,17,17,17

%N Difference between the closest square and the closest cube to n.

%C a(A201217(n)) = 0.

%H T. D. Noe, <a href="/A061023/b061023.txt">Table of n, a(n) for n = 0..10000</a>

%F a(n) = abs(A053187(n) - A201053(n)). [_Reinhard Zumkeller_, Nov 28 2011]

%e a(46)=15 because the nearest square is 49 and the nearest cube is 64 and 64 - 49 = 15.

%t dsc[n_]:=Module[{s=Floor[Sqrt[n]],c=Floor[Power[n, (3)^-1]],ns,nc}, ns= Nearest[{s^2,(s+1)^2},n]; nc=Nearest[{c^3,(c+1)^3},n];Abs[nc-ns]]; Flatten[ Array[dsc,100,0]] (* _Harvey P. Dale_, Aug 19 2011 *)

%o (PARI) { for (n=0, 10000, x=n^(1/2); s=floor(x)^2; t=ceil(x)^2; if (n-s > t-n, s=t); x=n^(1/3); c=floor(x)^3; d=ceil(x)^3; if (n-c > d-n, c=d); write("b061023.txt", n, " ", abs(c-s)) ) } \\ _Harry J. Smith_, Jul 16 2009

%o (Haskell)

%o a061023 n = abs (a053187 n - a201053 n)

%o a061023_list = map a061023 [0..]

%o -- _Reinhard Zumkeller_, Nov 28 2011

%Y Cf. A000290, A000578.

%K easy,nice,nonn,look

%O 0,4

%A Hareendra Yalamanchili (hyalaman(AT)mit.edu), May 24 2001

%E More terms from _Harvey P. Dale_, Aug 19 2011