A316325 Indices of 2's in A305389.

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

Author

N. J. A. Sloane, Jul 09 2018

Keywords

• nonn

Links

• Robert Israel, Table of n, a(n) for n = 1..10000

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).

Programs

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