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A215525 a(0)=a(1)=1, a(n) = a(n-1) + a(a(n-2) mod n).

%I A215525 #15 May 22 2025 10:21:35
%S A215525 1,1,2,3,5,8,16,17,18,36,54,57,73,81,84,100,105,205,305,405,413,429,
%T A215525 634,734,788,824,842,926,928,1854,2782,3606,6388,6424,9206,9611,10453,
%U A215525 11381,11384,17772,18560,18965,30349,30351,36775,37204,37633,38559,38560,75764
%N A215525 a(0)=a(1)=1, a(n) = a(n-1) + a(a(n-2) mod n).
%C A215525 Same formula, seed {0,1} : 0, 1, 1, 2, 3, 4, 6, 9, 15, 15, 19, 22, 31, 46, 48, 49, 49, 98, 144, 146, 149, 298, 396, 792, 823, 921, 1019, 1021, 1043, 1049, 1841, 2860
%C A215525 Same formula, seed {1,2} : 1, 2, 4, 8, 9, 17, 25, 33, 35, 60, 77, 94, 111, 119, 238, 476, 714, 715, 826, 937, 962, 1081, 1795, 1796, 2733, 3814, 3822, 3855, 4093, 7948
%H A215525 Ivan Neretin, <a href="/A215525/b215525.txt">Table of n, a(n) for n = 0..10000</a>
%F A215525 a(0)=a(1)=1, for n>=2, a(n) = a(n-1) + a(a(n-2) mod n).
%t A215525 Fold[Append[#1, #1[[-1]] + #1[[1 + Mod[#1[[-2]], #2]]]] &, {1, 1}, Range[2, 49]] (* _Ivan Neretin_, Sep 07 2017 *)
%o A215525 (Python)
%o A215525 a = [1]*1000
%o A215525 for n in range(2,77):
%o A215525   print(a[n-2],end=', ')
%o A215525   a[n] = a[n-1] + a[a[n-2] % n]
%o A215525 # Corrected by _Derek Orr_, Sep 25 2014
%Y A215525 Cf. A215488.
%K A215525 nonn,easy
%O A215525 0,3
%A A215525 _Alex Ratushnyak_, Aug 14 2012