OFFSET
0,3
LINKS
Rémy Sigrist, PARI program
FORMULA
a(n) <= A002275(n).
EXAMPLE
For n = 44:
- the number 44 could encode 1 or 2 runs of consecutive equal digits,
- for 1 run, we have the following possibilities:
11111111111111111111111111111111111111111111 (44 1's)
2222222222222222222222 (22 2's)
44444444444 (11 4's)
- for 2 runs, we have the following possibilities:
11114 (4 1's and then 1 4's)
224 (2 2's and then 1 4's)
111122 (4 1's and then 2 2's)
422 (1 4's and then 2 2's)
221111 (2 2's and then 4 1's)
41111 (1 4's and then 4 1's)
- the least possibility is 224,
- so a(44) = 224.
PROG
(PARI) See Links section.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Rémy Sigrist, Feb 22 2022
STATUS
approved