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 A227366 a(0)=1, a(n+1) = a(n) + a(n-1)*a(n-2) + a(n-3)*a(n-4)*a(n-5) + a(n-6)*a(n-7)*a(n-8)*a(n-9) + ... + ...*a(0). 4
 1, 1, 2, 3, 6, 13, 33, 118, 584, 4714, 76206, 2879841, 364389490, 220150411628, 1049813737275512, 80222580570107370160, 231117086585854944888597249, 84218767584329653007205530276477742, 18540809099930664963747242025045529905738135516 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS EXAMPLE a(1) = a(0) = 1 a(2) = a(1) + a(0) = 2 a(3) = a(2) + a(1)*a(0) = 3 a(4) = a(3) + a(2)*a(1) + a(0) = 3 + 2 + 1 = 6 a(5) = a(4) + a(3)*a(2) + a(1)*a(0) = 6 + 3*2 + 1 = 13 PROG (Python) a = [1]*99 for n in range(20):   sum = i = 0   k = 1   while i<=n:     product = 1     for x in range(k):       product *= a[n-i]       i += 1       if i>n: break     sum += product     k += 1   a[n+1] = sum   print(str(a[n]), end=', ') CROSSREFS Cf. A227363, A227364, A227365, A227367. Sequence in context: A296531 A220699 A202086 * A171878 A117403 A002877 Adjacent sequences:  A227363 A227364 A227365 * A227367 A227368 A227369 KEYWORD nonn,changed AUTHOR Alex Ratushnyak, Jul 08 2013 STATUS approved

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Last modified May 12 04:27 EDT 2021. Contains 343810 sequences. (Running on oeis4.)