OFFSET
1,3
COMMENTS
Observations:
The digits 0 and 1 appear only in terms 0 and 1, respectively.
Terms cannot contain two 2s, two 3s, a 2 and a 3, a 2 and a 4, a 3 and a 4, or a 4 and a 6.
Digits in each term appear in ascending order (A009994).
LINKS
Rémy Sigrist, Table of n, a(n) for n = 1..10000
Rémy Sigrist, PARI program for A343403
MAPLE
# product of digits
A007954 := proc(n::integer)
if n = 0 then
0;
else
mul( d, d=convert(n, base, 10)) ;
end if;
end proc:
hit:=Array(0..10000, -1);
a:=[0];
hit[0]:=0;
for n from 1 to 50000 do p:=A007954(n);
if p>0 and hit[p]=-1 then hit[p]:=n; a:=[op(a), n]; fi; od:
a; # N. J. A. Sloane, Apr 14 2021
PROG
(Python 3.7)
def getBaseTen(howMany=100):
listToReturn = []
listOfObtainedValues = []
count = 0
while len(listToReturn) < howMany:
afterOnePermutation = 1
for num in str(count):
afterOnePermutation *= int(num)
if afterOnePermutation is 0:
break
if not afterOnePermutation in listOfObtainedValues:
listToReturn.append(str(count))
listOfObtainedValues.append(afterOnePermutation)
count += 1
return listToReturn
(PARI) See Links section.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Collin King, Apr 14 2021
STATUS
approved