A349260 a(n) is the least number k such that A349258(k) = n.

1, 2, 6, 8, 24, 120, 216, 128, 384, 1920, 3456, 17280, 120960, 432000, 279936, 32768, 98304, 491520, 884736, 4423680, 30965760, 110592000, 71663616, 358318080, 2508226560, 8957952000, 62705664000, 689762304000, 3072577536000, 5598720000000, 470184984576, 2147483648

Offset

0,2

Links

Amiram Eldar, Table of n, a(n) for n = 0..111

Example

a(2) = 6 since A349258(6) = 2 and A349258(k) != 2 for all k < 6.

Mathematica

f[p_, e_] := 2^DigitCount[e, 2, 1] - 1; d[1] = 0; d[n_] := Plus @@ f @@@ FactorInteger[n]; seq[len_, nmax_] := Module[{s = Table[0, {len}], k = 0, n = 1, i}, While[k < len && n < nmax, i = d[n] + 1; If[i <= len && s[[i]] == 0, k++; s[[i]] = n]; n++]; TakeWhile[s, # > 0 &]]; seq[15, 10^6]

Crossrefs

Cf. A349258, A349259.

Sequence in context: A122756 A193946 A349259 * A189850 A189358 A116083

Adjacent sequences: A349257 A349258 A349259 * A349261 A349262 A349263

Keyword

nonn

Author

Amiram Eldar, Nov 12 2021

Status

approved