A376186
a(n) = denominator of the sum S(n) defined in A376184.
Original entry on oeis.org
8, 40, 680, 231880, 21507565640, 231287689900961870440, 21397598199889399837872215012598300187880, 228928604361955042169940915981517711585578107873998357253128210226981219949635080
Offset: 1
The initial values of S(n) are 5/8, 37/40, 677/680, 231877/231880, 21507565637/21507565640, 231287689900961870437/231287689900961870440, ...
Cf.
A004168,
A082732,
A374663,
A375516,
A375531,
A375532,
A375781,
A375522,
A376048-
A376062,
A376184,
A376185.
A376244
Lexicographically earliest sequence of positive integers a(1), a(2), ... with the property that the lexicographically earliest sequence of positive integers b(1), b(2), ... such that for any n > 0, S(n) = Sum_{k = 1..n} 1 / (a(k)*b(k)) < 1, also implies that S(n) is never of the form (e_n - 1) / e_n for some integer e_n.
Original entry on oeis.org
3, 4, 5, 4, 7, 3, 9, 1, 11, 4, 13, 7, 9, 19, 10, 2, 23, 25, 29, 27, 53, 1, 17, 7, 2, 2, 15, 67, 22, 37
Offset: 1
The initial terms are:
n a(n) b(n) S(n)
- ---- ------ ---------------------------
1 3 1 1/3
2 4 1 7/12
3 5 1 47/60
4 4 2 109/120
5 7 2 823/840
6 3 17 4757/4760
7 9 177 7582661/7582680
8 1 399089 3026164178509/3026164178520
Showing 1-2 of 2 results.
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