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A316326
Indices of 3's in A305389.
5
2, 4, 7, 8, 11, 13, 16, 18, 21, 22, 25, 27, 30, 33, 35, 38, 39, 42, 44, 47, 48, 51, 53, 56, 59, 61, 64, 65, 68, 70, 73, 75, 78, 79, 82, 84, 87, 90, 92, 95, 96, 99, 101, 104, 106, 109, 110, 113, 115, 118, 121, 123, 126, 127, 130, 132, 135, 136, 139, 141, 144, 147, 149, 152, 153, 156, 158, 161, 163, 166, 167, 170, 172
OFFSET
1,1
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]=3, [$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: A187834 A261619 A187575 * A074204 A030355 A288307
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Jul 09 2018
STATUS
approved