A282564 Real part of A000178(n) * Sum_{k=0..n} i^k/k!, where i = sqrt(-1).
1, 1, 1, 6, 156, 18720, 13443840, 67756953600, 2732085780480000, 991419288020582400000, 3597660477435617162035200000, 143607093745702043133526671360000000, 68788027941331539080620236035063808000000000, 428344480781652673551035086691251861743206400000000000
Offset: 0
Keywords
Examples
For n = 4, a(4) = 156, which is the real part of A000178(4)*(1/0! + i/1! - 1/2! - i/3! + 1/4!) = 156+240*i.
Links
- Daniel Suteu, Table of n, a(n) for n = 0..50
Programs
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PARI
a(n) = real(prod(k=0, n, k!) * sum(k=0, n, I^k/k!));