A248228 - OEIS

A248228

Numbers k such that A248227(k+1) = A248227(k).

1, 4, 8, 11, 14, 17, 21, 24, 27, 30, 34, 37, 40, 44, 47, 50, 53, 57, 60, 63, 66, 70, 73, 76, 79, 83, 86, 89, 92, 96, 99, 102, 105, 109, 112, 115, 119, 122, 125, 128, 132, 135, 138, 141, 145, 148, 151, 154, 158, 161, 164, 167, 171, 174, 177, 180, 184, 187

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OFFSET

1,2

COMMENTS

Since A248227(k+1) - A248227(k) is in {0,1} for k >= 1, A248228 and A248229 are complementary.

LINKS

Clark Kimberling, Table of n, a(n) for n = 1..300

EXAMPLE

The difference sequence of A248227 is (0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, ...), so that A248228 = (1, 4, 8, 11, 14, 17, 2,...) and A248229 = (2, 3, 5, 6, 7, 9, 10, 12, 13, 15, 16, 18,...), the complement of A248228.

MATHEMATICA

$MaxExtraPrecision = Infinity; z = 400; p[k_] := p[k] = Sum[1/h^4, {h, 1, k}];

N[Table[Zeta[4] - p[n], {n, 1, z/10}]]

f[n_] := f[n] = Select[Range[z], Zeta[4] - p[#] < 1/n^3 &, 1];

u = Flatten[Table[f[n], {n, 1, z}]] (* A248227 *)

Flatten[Position[Differences[u], 0]] (* A248228 *)

Flatten[Position[Differences[u], 1]] (* A248229 *)

f = Table[Floor[1/(Zeta[4] - p[n])], {n, 1, z}] (* A248230 *)

CROSSREFS

Cf. A248227, A248229, A248230.

Sequence in context: A072518 A113553 A342279 * A297464 A311034 A311035

Adjacent sequences: A248225 A248226 A248227 * A248229 A248230 A248231

KEYWORD

nonn,easy

AUTHOR

Clark Kimberling, Oct 05 2014

STATUS

approved