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A248776
Greatest 8th power integer that divides n!
3
1, 1, 1, 1, 1, 1, 1, 1, 1, 256, 256, 256, 256, 256, 256, 256, 256, 429981696, 429981696, 429981696, 429981696, 429981696, 429981696, 429981696, 429981696, 429981696, 429981696, 110075314176, 110075314176, 110075314176, 110075314176, 110075314176
OFFSET
1,10
COMMENTS
Every term divides all its successors.
LINKS
FORMULA
a(n) = n!/A248778(n).
EXAMPLE
a(8) = 128 because 128 divides 8! and if k > 2 then k^8 does not divide 8!.
MATHEMATICA
z = 60; f[n_] := f[n] = FactorInteger[n!]; r[m_, x_] := r[m, x] = m*Floor[x/m];
u[n_] := Table[f[n][[i, 1]], {i, 1, Length[f[n]]}];
v[n_] := Table[f[n][[i, 2]], {i, 1, Length[f[n]]}];
p[m_, n_] := p[m, n] = Product[u[n][[i]]^r[m, v[n]][[i]], {i, 1, Length[f[n]]}];
m = 8; Table[p[m, n], {n, 1, z}] (* A248776 *)
Table[p[m, n]^(1/m), {n, 1, z}] (* A248777 *)
Table[n!/p[m, n], {n, 1, z}] (* A248778 *)
Module[{e=Range[30]^8}, Table[Max[Select[e, Divisible[n!, #]&]], {n, 40}]] (* Harvey P. Dale, Dec 23 2019 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Oct 14 2014
STATUS
approved