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A186190
First digit of tribonacci sequence A000213.
2
1, 1, 1, 3, 5, 9, 1, 3, 5, 1, 1, 3, 6, 1, 2, 4, 7, 1, 2, 4, 8, 1, 2, 5, 9, 1, 3, 6, 1, 2, 3, 6, 1, 2, 4, 7, 1, 2, 4, 9, 1, 3, 5, 1, 1, 3, 6, 1, 2, 4, 7, 1, 2, 4, 8, 1, 2, 5, 9, 1, 3, 6, 1, 2, 3, 6, 1, 2, 4, 7, 1, 2, 4, 9, 1, 3, 5, 1, 1, 3, 6, 1, 2, 4, 7, 1, 2, 4, 8, 1, 2, 5, 9, 1, 3, 6, 1, 2, 3, 6, 1, 2, 4
OFFSET
0,4
COMMENTS
Sequence obeys the Benford law about distribution of first digit d in a sequence: P(d) = log_10(1+1/d).
EXAMPLE
a(10) = 1 since A000213(10) = 193.
MATHEMATICA
t = {1, 1, 1}; Do[AppendTo[t, t[[-1]] + t[[-2]] + t[[-3]]], {100}]; Table[IntegerDigits[i][[1]], {i, t}]
CROSSREFS
Sequence in context: A058642 A258086 A141251 * A019739 A101298 A296452
KEYWORD
nonn,base
AUTHOR
Carmine Suriano, Feb 14 2011
EXTENSIONS
Offset changed by Georg Fischer, Jun 26 2024
STATUS
approved