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editing
proposed
a(1) = 1; a(n + 1) = 1 + productProduct_{k=1 to ..n-1} a(k) (mod n-1).
1, 1, 2, 3, 3, 4, 1, 3, 1, 1, 7, 6, 1, 12, 1, 10, 1, 12, 1, 3, 1, 1, 21, 12, 1, 6, 21, 1, 1, 15, 1, 20, 1, 31, 15, 1, 1, 32, 13, 1, 1, 18, 1, 7, 25, 1, 17, 38, 1, 1, 1, 1, 1, 26, 1, 6, 1, 1, 29, 47, 1, 42, 1, 1, 1, 1, 61, 26, 1, 25, 1, 21, 1, 64, 21, 1, 1, 29, 1, 18, 1, 1, 11, 21, 1, 1, 59, 1, 1, 39, 1, 1, 5, 1, 1, 1, 1, 32, 1, 1, 1, 42, 1, 9, 1, 1, 29, 55, 1, 44, 1, 37, 1, 105, 1, 101, 1, 1, 1, 1, 1, 1, 1, 100
Note that the running product for each a(n+1) is incrementally taken computed mod n-1.
Inspired by A066910.
proposed
editing
editing
proposed
allocated for Matt Donahoea(1) = 1; a(n + 1) = 1 + product{k=1 to n} a(k) (mod n)
1, 1, 2, 3, 3, 4, 1, 3, 1, 1, 7, 6, 1, 12, 1, 10, 1, 12, 1, 3, 1, 1, 21, 12, 1, 6, 21, 1, 1, 15, 1, 20, 1, 31, 15, 1, 1, 32, 13, 1, 1, 18, 1, 7, 25, 1, 17, 38, 1, 1, 1, 1, 1, 26, 1, 6, 1, 1, 29, 47, 1, 42, 1, 1, 1, 1, 61, 26, 1, 25, 1, 21, 1, 64, 21, 1, 1, 29, 1, 18, 1, 1, 11, 21, 1, 1, 59, 1, 1, 39, 1, 1, 5, 1, 1, 1, 1, 32, 1, 1, 1, 42, 1, 9, 1, 1, 29, 55, 1, 44, 1, 37, 1, 105, 1, 101, 1, 1, 1, 1, 1, 1, 1, 100
1,3
Note that the running product for each a(n+1) is incrementally taken mod n
(Python)
def f(n):
if n == 1: return 1
a = 1
for k in range(1, n):
a = a * f(k) % (n - 1)
return a + 1
Inspired by A066910
allocated
nonn
Matt Donahoe, Aug 22 2020
approved
editing
allocated for Matt Donahoe
allocated
approved