

A343645


a(n) is the product of the frequencies of each digit of n up to and including that digit.


2



1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 12, 10, 12, 14, 16, 18, 20, 22, 24, 6, 52, 30, 21, 24, 27, 30, 33, 36, 39, 12, 70, 84, 56, 36, 40, 44, 48, 52, 56, 20, 90, 105, 120, 90, 55, 60, 65, 70, 75, 30, 112, 128, 144, 160, 132, 78, 84, 90, 96, 42, 136, 153, 170, 187, 204, 182
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,10


LINKS



EXAMPLE

a(10) = 2 as the digit 1 is the second digit 1 and the digit 0 is the first digit 0 giving 2*1.


PROG

(PARI) first(n) = my(v=vector(10), res=vector(n)); for(i=1, n, c=1; d=digits(i); for(i=1, #d, v[d[i]+1]++; c*=v[d[i]+1]); res[i] = c); res
(Python)
def aupto(limit):
f, alst = [0 for i in range(10)], []
for n in range(1, limit+1):
p = 1
for d in list(map(int, str(n))): f[d] += 1; p *= f[d]
alst.append(p)
return alst


CROSSREFS



KEYWORD

nonn,easy,base


AUTHOR



STATUS

approved



