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A103708
a(n+1) = d(n)+9 where d(n) is the n-th decimal digit in the concatenation of the digits in the sequence, starting with a(1)=1.
8
1, 10, 10, 9, 10, 9, 18, 10, 9, 18, 10, 17, 10, 9, 18, 10, 17, 10, 9, 10, 16, 10, 9, 18, 10, 17, 10, 9, 10, 16, 10, 9, 18, 10, 9, 10, 15, 10, 9, 18, 10, 17, 10, 9, 10, 16, 10, 9, 18, 10, 9, 10, 15, 10, 9, 18, 10, 17, 10, 9, 18, 10, 9, 10, 14, 10, 9, 18, 10, 17, 10, 9, 10, 16, 10, 9, 18, 10
OFFSET
1,2
LINKS
MAPLE
with(queue):
Q:= new(1): R:= 1:
for iter from 1 to 100 do
v:= dequeue(Q)+9;
R:= R, v;
L:= convert(v, base, 10);
for i from 1 to nops(L) do enqueue(Q, L[-i]) od;
od:
R; # Robert Israel, Jul 06 2020
MATHEMATICA
Flatten[ NestList[ Function[x, Flatten[ IntegerDigits[x] + 9]], {1}, 8]]
KEYWORD
base,nonn
AUTHOR
Robert G. Wilson v, Feb 12 2005
EXTENSIONS
Edited and corrected by Robert Israel, Jul 06 2020
STATUS
approved