[seqfan] Directly find pandigital numbers

Maurice.Clerc at WriteMe.com Maurice.Clerc at WriteMe.com
Wed Mar 2 11:01:11 CET 2022


As I am a newcomer on this list, and, moreover, and since integer 
sequences aren’t my usual research field, the following problem may have 
already been solved without my knowledge.
Anyway, here it is.

Let us consider pandigital numbers with d digits in base b, possibly 
with leading zeros.
Here 'pandigital' means: contains each of the digits from 0 to b-1 at 
least once.

Examples(d=5,b=4):
03221 is pandigital
03322 is not
30102 is pandigital

For d=5, b=4, the sequence S(d,b) of such pandigital numbers is (thanks 
Mathematica!):
00321,01023,01032,01123,01132,01203,01213,01223, ...

Or, in base 10:
57,75,78,91,94,99,103,107, ...
(BTW this sequence is not in OEIS).

Let us call S(d,b)(n) the n-th element of the sequence.
Is there a formula to directly compute S(d,b)(n+1) as a function of 
S(d,b)(n)?
Or, even better, to directly compute S(d,b)(n) for a given n?

Maurice




More information about the SeqFan mailing list