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a(n) = (A005867(n+1) - A000165(n))/96.
0

%I #13 Sep 02 2023 16:59:47

%S 0,0,0,0,1,20,480,10560,272640,8709120,280627200,10644480000,

%T 439404134400,18781972070400,873535419187200,45751167221760000,

%U 2665172872986624000,160281737951182848000,10593163661832880128000

%N a(n) = (A005867(n+1) - A000165(n))/96.

%C A005867 can be generated recursively using A006093 and A000165 can be generated recursively using the even numbers. Since all primes after 2 are odd, (A005867 - A000165)/96 is an integer.

%e A005867(n+1) begins 1, 2, 8, 48, 480, 5760, 92160, ...

%e A000165(n) begins 1, 2, 8, 48, 384, 3840, 46080, ...

%e difference begins 0, 0, 0, 0, 96, 1920, 46080, ... .

%Y Cf. A000165, A005867, A006093.

%K easy,nonn

%O 0,6

%A _Alford Arnold_, Nov 23 2001

%E More terms from _Jason Earls_, Apr 23 2002