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a(n) = Product_{k=1..n} (169 - 13/k).
0

%I #10 Jan 03 2021 14:08:38

%S 1,156,25350,4174300,691890225,115130533440,19207610662240,

%T 3210414924974400,537343198067590200,90034838076214002400,

%U 15098842345381088202480,2533860269961226256525280,425477370330989242241536600,71480198215606192696578148800

%N a(n) = Product_{k=1..n} (169 - 13/k).

%C This sequence is generalizable: Product_{k=1..n} (q^2 - q/k) = (q^n/n!) * Product_{k=0..n-1} (q*k + q-1) = expansion of (1- x*q^2)^((1-q)/q).

%p seq(product(169-13/k, k=1.. n), n=0..20);

%p seq((13^n/n!)*product(13*k+12, k=0.. n-1), n=0..20);

%t Table[Product[169-13/k,{k,n}],{n,0,20}] (* _Harvey P. Dale_, Mar 13 2013 *)

%Y Cf. A004988, A049382, A004994, A216702, A216703, A216704, A216705, A216706, A216786, A216787.

%K nonn

%O 0,2

%A _Michel Lagneau_, Sep 16 2012