A392122 Numbers k such that (k^3 - greatest prime < k^3) > (-k^3 + least prime > k^3).

3, 5, 7, 13, 22, 24, 25, 29, 32, 39, 42, 44, 45, 50, 52, 56, 59, 61, 62, 63, 64, 65, 69, 71, 73, 75, 76, 79, 81, 83, 85, 86, 87, 88, 89, 92, 93, 94, 96, 98, 100, 103, 104, 105, 107, 113, 115, 123, 133, 138, 139, 140, 142, 143, 146, 150, 153, 154, 159, 163

Offset

1,1

Comments

Numbers k such that k^3 is in A264719. - Robert Israel, Jan 28 2026

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Maple

g:= proc(n) nextprime(n) + prevprime(n) < 2*n end proc:
select(k -> g(k^3), [$2..200]); # Robert Israel, Jan 28 2026

Mathematica

z = 600; f[x_] := f[x] = x^3;
u[n_] := NextPrime[f[n], -1]; v[n_] := NextPrime[f[n]];
s1 = Select[Range[z], f[#] - v[#] < u[#] - f[#] &]   (* A392120 *)
s2 = Select[Range[z], f[#] - v[#] == u[#] - f[#] &]  (* A075191 *)
s3 = Select[Range[z], f[#] - v[#] > u[#] - f[#] &]   (* A392122 *)

Crossrefs

Cf. A264719, A390788, A392120, A392121.

Sequence in context: A347834 A060274 A345130 * A005235 A353284 A107664

Adjacent sequences: A392119 A392120 A392121 * A392123 A392124 A392125

Keyword

nonn

Author

Clark Kimberling, Jan 18 2026

Extensions

1 removed by Sean A. Irvine, Jan 28 2026

Status

approved