cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A341107 a(n) = A341108(n)/A195441(n).

Original entry on oeis.org

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

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Author

Peter Luschny, Feb 07 2021

Keywords

Crossrefs

Programs

  • 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)])
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