OFFSET
1,2
COMMENTS
Numbers whose digits can be generated by successively throwing a regular die with the numbers 1..6 and concatenating the results.
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
FORMULA
a(n+1) = 1 + (if a(n) mod 10 < 6 then a(n) else a(a(n)\10)*10), a(0)=1. - Reinhard Zumkeller, Jul 13 2007
EXAMPLE
The number 61 can be generated by throwing a die twice and combining the results, but 17 not.
MATHEMATICA
Select[Range[200], Max[IntegerDigits[#]]<=6&& DigitCount[#, 10, 0] ==0&] (* Harvey P. Dale, Apr 04 2011 *)
FromDigits/@Flatten[Table[Tuples[Range[6], n], {n, 3}], 1] (* Harvey P. Dale, Jul 26 2015 *)
PROG
(Haskell)
import Data.List (intersect)
a057436 n = a057436_list !! (n-1)
a057436_list = filter (null . (intersect "0789") . show) [1..]
-- Reinhard Zumkeller, Mar 28 20012
(Python)
from itertools import product
A057436_list = [int(''.join(d)) for l in range(1, 5) for d in product('123456', repeat=l)] # Chai Wah Wu, Sep 01 2021
CROSSREFS
KEYWORD
easy,nice,nonn,base
AUTHOR
Thomas Schulze (jazariel(AT)tiscalenet.it), Sep 08 2000
EXTENSIONS
Offset corrected by Reinhard Zumkeller, Aug 16 2011
STATUS
approved