A179792 Values y for records of the minima of the positive distance d between the ninth power of a positive integer x and the square of an integer y such that d = x^9 - y^2 (x <> k^2 and y <> k^9).

22, 140, 1397, 3174, 11585, 102978, 1098758, 1342070, 2761448, 116348986, 326908123, 5661454305, 14439547606, 24195364585, 44988513611, 1037782490126, 18907836782131, 50577039498042, 476237361126871, 10815891488601655

Offset

1,1

Comments

Distance d is equal to 0 when x = k^2 and y = k^9.

For d values see A179790.

For x values see A179791.

Conjecture (Artur Jasinski): For any positive number x >= A179791(n), the distance d between the ninth power of x and the square of any y (such that x <> k^2 and y <> k^9) can't be less than A179790(n).

Links

Table of n, a(n) for n=1..20.

Mathematica

d = 9; max = 1000; vecd = Table[10^100, {n, 1, max}]; vecx = Table[10^100, {n, 1, max}]; vecy = Table[10^100, {n, 1, max}]; len = 1; Do[m = Floor[(n^d)^(1/2)]; k = n^d - m^2; If[k != 0, ile = 0; Do[If[vecd[[z]] < k, ile = ile + 1], {z, 1, len}]; len = ile + 1; vecd[[len]] = k; vecx[[len]] = n; vecy[[len]] = m], {n, 1, 10000000}]; dd = {}; xx = {}; yy = {}; Do[AppendTo[dd, vecd[[n]]]; AppendTo[xx, vecx[[n]]]; AppendTo[yy, vecy[[n]]], {n, 1, len}]; yy

Crossrefs

Cf. A179107, A179108, A179109, A179386, A179387, A179388, A179407, A179408, A179784, A179785, A179786, A179790, A179791, A179792, A179793, A179794, A179795.

Sequence in context: A238170 A275799 A185397 * A125332 A126490 A200776

Adjacent sequences: A179789 A179790 A179791 * A179793 A179794 A179795

Keyword

nonn

Author

Artur Jasinski, Jul 27 2010

Status

approved