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A227364 a(n) = 1 + 2*3 + 4*5*6 + 7*8*9*10 + ... + ...*n (see Example lines).

%I A227364 #28 May 04 2021 07:37:28
%S A227364 0,1,3,7,11,27,127,134,183,631,5167,5178,5299,6883,29191,365527,
%T A227364 365543,365799,370423,458551,2226007,39435607,39435629,39436113,
%U A227364 39447751,39739207,47329207,252562807,6006997207,6006997236,6006998077,6007024177,6007860247,6035477527,6975328087
%N A227364 a(n) = 1 + 2*3 + 4*5*6 + 7*8*9*10 + ... + ...*n  (see Example lines).
%H A227364 Seiichi Manyama, <a href="/A227364/b227364.txt">Table of n, a(n) for n = 0..10000</a>
%e A227364 a(5) = 1 + 2*3 + 4*5 = 27;
%e A227364 a(6) = 1 + 2*3 + 4*5*6 = 127;
%e A227364 a(7) = 1 + 2*3 + 4*5*6 + 7 = 134.
%o A227364 (Python)
%o A227364 for n in range(55):
%o A227364   sum = 0
%o A227364   i = k = 1
%o A227364   while i<=n:
%o A227364     product = 1
%o A227364     for x in range(k):
%o A227364       product *= i
%o A227364       i += 1
%o A227364       if i>n: break
%o A227364     sum += product
%o A227364     k += 1
%o A227364   print(str(sum), end=',')
%Y A227364 Cf. A227363, A227365, A227366, A227367, A228958.
%K A227364 nonn
%O A227364 0,3
%A A227364 _Alex Ratushnyak_, Jul 07 2013