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reviewed
approved
proposed
reviewed
editing
proposed
(Python)
from itertools import chain, count, islice
def altgen(seed, digits):
allowed = "02468" if seed in "13579" else "13579"
if digits == 1: yield from allowed; return
for f in allowed: yield from (f + r for r in altgen(f, digits-1))
def agen(): yield from chain(range(10), (int(f+r) for d in count(2) for f in "123456789" for r in altgen(f, d-1)))
print(list(islice(agen(), 65))) # Michael S. Branicky, Jul 12 2022
approved
editing
proposed
approved
editing
proposed
(Python)
from itertools import count
def A030141_gen(startvalue=0): # generator of terms >= startvalue
return filter(lambda n:all(int(a)+int(b)&1 for a, b in zip(str(n), str(n)[1:])), count(max(startvalue, 0)))
A030141_list = list(islice(A030141_gen(), 30)) # Chai Wah Wu, Jul 12 2022
reviewed
editing
proposed
reviewed
editing
proposed
(Python)
from itertools import count, islice, accumulate
def A030141_gen(startvalue=0): # generator of terms >= startvalue
return filter(lambda n:all(map(lambda n:n&1, islice(accumulate(int(d) for d in str(n)), 1, None))), count(max(startvalue, 0)))
A030141_list = list(islice(A030141_gen(), 30)) # Chai Wah Wu, Jul 11 2022
proposed
editing