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A341107
a(n) = A341108(n)/A195441(n).
3
1, 1, 2, 4, 8, 8, 96, 192, 1152, 384, 1536, 1536, 18432, 18432, 73728, 147456, 884736, 884736, 10616832, 10616832, 212336640, 212336640, 2548039680, 849346560, 152882380800, 30576476160, 366917713920, 40768634880, 163074539520, 163074539520, 1956894474240
OFFSET
0,3
PROG
(Sage)
def A341107(n):
def L(n, p, r):
s, q = 0, p - r
while q <= n:
s += n // q
q *= p
return s
if n < 2: return 1
p = prod(p^(L(n, p, 1) - L(n+1, p, 0)) for p in primes(n+1))
q = prod(p for p in prime_divisors(n + 1))
r = prod(p for p in (2..(n + 2)//(2 + n % 2))
if is_prime(p) and sum((n+1).digits(base = p)) >= p)
return ((n + 1) * p) // (q * r)
print([A341107(n) for n in (0..30)])
CROSSREFS
KEYWORD
nonn
AUTHOR
Peter Luschny, Feb 07 2021
STATUS
approved