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A377231
a(n) = digital root of 2^Fibonacci(n).
0
1, 2, 2, 4, 8, 5, 4, 2, 8, 7, 2, 5, 1, 5, 5, 7, 8, 2, 7, 5, 8, 4, 5, 2, 1, 2, 2, 4, 8, 5, 4, 2, 8, 7, 2, 5, 1, 5, 5, 7, 8, 2, 7, 5, 8, 4, 5, 2, 1, 2, 2, 4, 8, 5, 4, 2, 8, 7, 2, 5, 1, 5, 5, 7, 8, 2, 7, 5, 8, 4, 5, 2, 1, 2, 2, 4, 8, 5, 4, 2, 8, 7, 2, 5, 1, 5, 5, 7, 8, 2, 7, 5, 8, 4, 5, 2
OFFSET
0,2
COMMENTS
This sequence has period 24.
LINKS
Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1).
FORMULA
a(n) = (a(n-1) * a(n-2) - 1) mod 9 + 1.
a(n) = A010888(A000301(n)).
MATHEMATICA
Module[{a, n}, RecurrenceTable[{a[n] == Mod[a[n-1]*a[n-2] - 1, 9] + 1, a[0] == 1, a[1] == 2}, a, {n, 0, 99}]] (* or *)
PadRight[{}, 100, {1, 2, 2, 4, 8, 5, 4, 2, 8, 7, 2, 5, 1, 5, 5, 7, 8, 2, 7, 5, 8, 4, 5, 2}] (* Paolo Xausa, Nov 08 2024 *)
CROSSREFS
Sequence in context: A077964 A077968 A123958 * A048572 A337561 A121173
KEYWORD
nonn,easy,base
AUTHOR
Robert Bruce Gray, Oct 20 2024
STATUS
approved