|
| |
|
|
A347496
|
|
Primorial base Niven numbers (A333426) with a record gap to the next primorial base Niven number.
|
|
1
|
|
|
|
1, 2, 9, 12, 25, 50, 120, 344, 400, 770, 1120, 3920, 13566, 13734, 19845, 22748, 148148, 167854, 176220, 889896, 2946216, 3685416, 5072256, 7139280, 8521056, 9058900, 9625336, 17825857, 19392072, 27504848, 76952788, 106691001, 162789696, 198582784, 212847225
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,2
|
|
|
COMMENTS
|
The corresponding gaps are 1, 2, 3, 4, 5, 10, 12, 16, 20, 34, 37, 48, 54, 66, 75, 121, 132, 146, 180, 238, 241, 248, 288, 302, 314, 332, 336, 343, 348, 400, 476, 479, 484, 496, 500, ...
|
|
|
LINKS
|
Table of n, a(n) for n=1..35.
|
|
|
EXAMPLE
|
The first 8 primorial base Niven numbers are 1, 2, 4, 6, 8, 9, 12 and 16. The gaps between them are 1, 2, 2, 2, 1, 3 and 4. The record gaps, 1, 2, 3 and 4, occur after the terms 1, 2, 9 and 12.
|
|
|
MATHEMATICA
|
max = 7; bases = Prime @ Range[max, 1, -1]; nmax = Times @@ bases - 1; sumdig[n_] := Plus @@ IntegerDigits[n, MixedRadix[bases]]; primoNivenQ[n_] := Divisible[n, sumdig[n]]; gapmax = 0; n1 = 1; s = {}; Do[If[primoNivenQ[n], gap = n - n1; If[gap > gapmax, gapmax = gap; AppendTo[s, n1]]; n1 = n], {n, 2, nmax}]; s
|
|
|
CROSSREFS
|
Cf. A333426, A333427, A337076, A337077, A347495.
Sequence in context: A053900 A318681 A183207 * A304797 A337360 A340038
Adjacent sequences: A347493 A347494 A347495 * A347497 A347498 A347499
|
|
|
KEYWORD
|
nonn,base
|
|
|
AUTHOR
|
Amiram Eldar, Sep 03 2021
|
|
|
STATUS
|
approved
|
| |
|
|
