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A330615
a(0) = 1; a(1) = 1; a(n) = a(a(n - 1) mod n) + a(a(n - 2) mod n).
1
1, 1, 2, 3, 5, 4, 9, 7, 8, 15, 12, 6, 10, 21, 19, 14, 22, 23, 9, 20, 16, 38, 44, 52, 21, 40, 57, 24, 22, 65, 48, 26, 79, 78, 18, 17, 32, 102, 136, 41, 23, 53, 58, 26, 76, 83, 150, 47, 56, 54, 14, 22, 63, 56, 17, 24, 44, 97, 117, 253, 118, 112, 58, 171, 143, 74
OFFSET
0,3
COMMENTS
Periodic with period 63584 starting at n = 441329.
EXAMPLE
n = 8: a(7) = 7, a(6) = 9, so a(8) = a(a(7) mod 8) + a(a(6) mod 8) = a(7 mod 8) + a(9 mod 8) = a(7) + a(1) = 7 + 1 = 8.
MATHEMATICA
a[0] = a[1] = 1; a[n_] := a[n] = a[Mod[a[n-1], n]] + a[Mod[a[n-2], n]]; Array[a, 66, 0] (* Amiram Eldar, Dec 21 2019 *)
PROG
(Python 3) # Lists terms up to given n.
def a_list(n):
a=[1, 1]
for k in range(2, n+1):
a.append(a[a[-1]%k]+a[a[-2]%k])
return a
CROSSREFS
Cf. A308818 (similar sequence with initial conditions a(0) = 2, a(1) = 3).
Sequence in context: A096116 A259431 A085875 * A302850 A338253 A060030
KEYWORD
nonn
AUTHOR
Jack Kiuttu, Dec 20 2019
STATUS
approved