A060398 Values of k associated with A060397.

1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 2, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 2, 1, 0, 0, 1, 0, 2, 1, 0, 0, 1, 0, 1, 1, 0, 2, 1, 0, 0, 1, 0, 4, 1, 0, 3, 1, 0, 1, 1, 0, 2, 1, 0, 0, 1, 0, 1, 1, 0, 2, 1, 0, 1, 1, 0, 2, 1, 0, 0, 1, 0, 0, 1, 0, 4, 1, 0, 1, 1, 0, 2, 1, 0, 0, 1, 0, 3, 1, 0, 2, 1, 0, 1, 1, 0, 2

Offset

0,15

Links

T. D. Noe, Table of n, a(n) for n = 0..10000

Carlos Rivera, Conjecture 17. The Ludovicus conjecture about the Euler trinomials, The Prime Puzzles & Problems Connection.

Mathematica

a[n_] := Switch[n, 0, 1, _, Module[{f, kmax0 = 2}, f[kmax_] := f[kmax] = MinimalBy[Table[{k, FactorInteger[k^2 + k + 2 n + 1][[1, 1]]}, {k, 0, kmax}], Last, 1]; f[kmax = kmax0]; f[kmax = 2 kmax]; While[f[kmax] != f[kmax/2], kmax = 2 kmax]; f[kmax][[1, 1]]]];
Table[a[n], {n, 0, 105}] (* Jean-François Alcover, Aug 15 2022 *)

Crossrefs

Cf. A060397.

Sequence in context: A086017 A350532 A000161 * A253242 A359814 A359815

Adjacent sequences: A060395 A060396 A060397 * A060399 A060400 A060401

Keyword

nonn,easy

Author

N. J. A. Sloane, Apr 04 2001

Extensions

More terms from T. D. Noe, Mar 12 2007

Status

approved