close
login
A144364
Where records occur in A144261.
4
1, 11, 31, 53, 331, 377, 983, 1499, 2609, 3329, 6637, 6997, 19937, 34987, 157961, 173699, 256661, 1349923, 1616359, 1993333, 2199833, 5794969, 6906869, 12204431, 14223073, 20666551, 168499997, 4819002127, 7331752277, 8259275501, 27017515331, 27581017543
OFFSET
1,2
LINKS
MATHEMATICA
f[n_] := Module[{k = 1, m = n}, While[!Divisible[m, DigitSum[m]], m +=n; k++]; k]; seq[lim_] := Module[{s = {}, fm = 0, fi}, Do[fi = f[i]; If[fi > fm, fm = fi; AppendTo[s, i]], {i, 1, lim}]; s]; seq[10^5] (* Amiram Eldar, Jun 30 2025 *)
PROG
(PARI) f(n) = {my(k = 1, m = n); while(m % sumdigits(m), m +=n; k++); k; }
list(lim) = my(fm = 0, fi); for(i = 1, lim, fi = f(i); if(fi > fm, fm = fi; print1(i, ", "))); \\ Amiram Eldar, Jun 30 2025
CROSSREFS
Cf. A005349 (Niven numbers), A144261 (smallest k such that k*n is a Niven number), A144363 (records in A144261).
Sequence in context: A232764 A057630 A057628 * A226922 A031372 A028877
KEYWORD
base,nonn
AUTHOR
Klaus Brockhaus, Sep 19 2008
EXTENSIONS
a(27)-a(30) from Donovan Johnson, Jul 20 2010
a(31)-a(32) from Amiram Eldar, Jun 30 2025
STATUS
approved