A306569 a(n) is the largest value obtained by iterating x -> noz(x * n) starting from 1 (where noz(k) = A004719(k) omits the zeros from k) if any, otherwise a(n) = -1.
1, 765257552, 4858337151, 62987487698944, 14281197489647865625, 16756687971893376, 956884714362661, 292452281337511936, 11897243269649199, 1, 824281567746336491, 13552472793415699584, 841944776182612378933, 9434962871842528764976
Offset: 1
Examples
a(2) = max(A242350) = 765257552.
Links
- Rémy Sigrist, Table of n, a(n) for n = 1..250
- Rémy Sigrist, PARI program for A306569
Programs
-
PARI
See Links section.
Formula
a(10^k) = 1 for any k >= 0.
a(10*n) = a(n) for any n > 0.
Comments