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A334636
Number of different values of (x_n, x_1*x_2*...*x_n) where x_1=1 and x_i-x_{i-1} is 0 or 1.
1
1, 2, 4, 8, 16, 31, 59, 110, 202, 366, 653, 1143, 1961, 3303, 5480, 8992, 14647, 23742, 38334, 61648, 98700, 157265, 249397, 393814, 619611, 971988, 1521015, 2374946, 3700290, 5751806, 8916890, 13780598, 21220014, 32540179, 49668909, 75435401
OFFSET
1,2
PROG
(Python3)
k=[{(1, 1)}]
for i in range(20):
k.append(set([(i[0]*i[1], i[1]) for i in k[-1]])|set([(i[0]*(i[1]+1), i[1]+1) for i in k[-1]]))
[len(i) for i in k]
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Jack Zhang, Sep 10 2020
EXTENSIONS
a(31)-a(36) from Bert Dobbelaere, Oct 19 2020
STATUS
approved