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A316325
Indices of 2's in A305389.
5
1, 3, 6, 10, 12, 15, 17, 20, 24, 26, 29, 32, 34, 37, 41, 43, 46, 50, 52, 55, 58, 60, 63, 67, 69, 72, 74, 77, 81, 83, 86, 89, 91, 94, 98, 100, 103, 105, 108, 112, 114, 117, 120, 122, 125, 129, 131, 134, 138, 140, 143, 146, 148, 151, 155, 157, 160, 162, 165
OFFSET
1,2
LINKS
MAPLE
f:= 'f':
f(1):= 2: f(2):= 3: f(3):= (1, 2, 3):
S:= [1];
for i from 1 to 5 do T:= map(f, S); U:= map(f, T); S:= map(f, U); od:
select(t -> S[t+1]=2, [$0..nops(S)-1]); # Robert Israel, May 07 2019
CROSSREFS
Cf. A305389.
A316324, A316325, A316326 have the same relation to A305389 as A003144, A003145, A003146 do to the ternary tribonacci word A080843 (or A092782).
Sequence in context: A301285 A310042 A310043 * A114981 A319452 A187744
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Jul 09 2018
STATUS
approved