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A061023
Difference between the closest square and the closest cube to n.
5
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, 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, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 17, 17, 17, 17, 17, 17
OFFSET
0,4
COMMENTS
a(A201217(n)) = 0.
FORMULA
a(n) = abs(A053187(n) - A201053(n)). [Reinhard Zumkeller, Nov 28 2011]
EXAMPLE
a(46)=15 because the nearest square is 49 and the nearest cube is 64 and 64 - 49 = 15.
MATHEMATICA
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 *)
PROG
(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
(Haskell)
a061023 n = abs (a053187 n - a201053 n)
a061023_list = map a061023 [0..]
-- Reinhard Zumkeller, Nov 28 2011
CROSSREFS
Sequence in context: A351348 A246011 A329310 * A355954 A057690 A318706
KEYWORD
easy,nice,nonn,look
AUTHOR
Hareendra Yalamanchili (hyalaman(AT)mit.edu), May 24 2001
EXTENSIONS
More terms from Harvey P. Dale, Aug 19 2011
STATUS
approved