OFFSET
1,3
COMMENTS
A positive integer n is a base-b digit-sum-multiple (DSM) number if the sum of the digits of n, in base b, divides n. It is a deletable base-b DSM if it has the property that removing some digit leaves either the empty string or another deletable base-b DSM.
PROG
(Python)
from itertools import count, islice
def ok(n, prevset):
b = bin(n)[2:]
if n%b.count("1"): return False
si = (b[:i]+b[i+1:] for i in range(len(b)))
return any(t[0] != '0' and int(t, 2) in prevset for t in si)
def agen(): # generator of terms
s, snxt = {1}, set()
for n in count(2):
yield len(s)
for i in range(2**(n-1), 2**n):
if ok(i, s):
snxt.add(i)
s, snxt = snxt, set()
print(list(islice(agen(), 20))) # Michael S. Branicky, Feb 25 2023
CROSSREFS
KEYWORD
nonn,base,more
AUTHOR
John W. Layman, Dec 14 2004
EXTENSIONS
a(19)-a(32) from Michael S. Branicky, Feb 25 2023
STATUS
approved