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a(n) = Product_{m=1..n} (binomial(n,m)+1).
6

%I #17 Apr 26 2024 02:24:06

%S 1,2,6,32,350,8712,526848,80289792,31428168318,31906468445000,

%T 84447578671097576,584524457418427932672,10604795873304968964262400,

%U 505245441738743508813986275328,63320582170435750241601032951040000,20908669294849228879861552351685432573952

%N a(n) = Product_{m=1..n} (binomial(n,m)+1).

%D V. K. Kharchenko, Fixed rings and noncommutative invariant theory, pp. 359-398 of M. Hazewinkel, ed., Handbook of Algebra, Vol. 2, Elsevier, 2000.

%H Reinhard Zumkeller, <a href="/A055612/b055612.txt">Table of n, a(n) for n = 0..69</a>

%F a(n) = A129824(n) / 2. - _Reinhard Zumkeller_, Jan 31 2015

%t Array[Product[1 + Binomial[#, m], {m, #}] &, 16, 0] (* _Michael De Vlieger_, Oct 30 2017 *)

%o (Haskell)

%o a055612 = product . map (+ 1) . tail . a007318_row

%o -- _Reinhard Zumkeller_, Jan 31 2015

%o (PARI) a(n) = prod(m=1, n, 1+binomial(n, m)); \\ _Michel Marcus_, Oct 30 2017

%Y Cf. A007318, A217716, A293954, A293955.

%K nonn

%O 0,2

%A _N. J. A. Sloane_, Jun 03 2000