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A364198
Index of first occurrence of n in A364197.
2
0, 1, 3, 6, 11, 16, 26, 43, 69, 115, 141, 158, 208, 293, 358, 440, 541, 642, 743, 1117, 1378, 1612, 1826, 2052, 2494, 2856, 3181, 3703, 4107, 4862, 5347, 5924, 6454, 7645, 8322, 8999, 9784, 10941, 12458, 13580, 14542, 15839, 16864, 18309, 19876, 21696, 23311, 25408, 28377, 30314
OFFSET
0,3
FORMULA
a(n) ~ n^3/3 (conjectured).
MATHEMATICA
s[0] = 0; s[n_] := s[n] = s[Abs[n - 1 - s[n - 1]^2]] + 1; TakeWhile[Flatten[FirstPosition[Array[s, 32000, 0] , #] & /@ Range[0, 50]] - 1 , NumberQ] (* Amiram Eldar, Jul 13 2023 *)
PROG
(Python)
a = [0]; [a.append(a[abs(n-a[n]**2)]+1) for n in range(1000)] # A364197
b = [a.index(n) for n in range(max(a)+1)] # A364198
CROSSREFS
Cf. A364197.
Sequence in context: A366969 A075703 A267583 * A277023 A034029 A310115
KEYWORD
nonn
AUTHOR
Rok Cestnik, Jul 13 2023
STATUS
approved