

A284212


The successive digits of the sequence are the same digits that have a prime rank in the sequence.


1



1, 11, 2, 10, 20, 3, 4, 100, 5, 6, 7, 200, 8, 9, 13, 12, 14, 24, 21, 15, 16, 30, 17, 40, 25, 18, 26, 19, 22, 27, 23, 28, 32, 50, 29, 31, 60, 33, 38, 39, 34, 35, 41, 36, 43, 37, 42, 51, 44, 45, 46, 52, 47, 61, 54, 48, 62, 64, 49, 72, 53, 55, 56, 57, 58, 59, 71, 63, 81, 65, 66, 75, 91, 67, 68, 69, 70
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OFFSET

1,2


COMMENTS

The sequence is started with a(1) = 1 and always extended with the smallest integer not yet present and not leading to a contradiction.


LINKS

JeanMarc Falcoz, Table of n, a(n) for n = 1..3002


EXAMPLE

The first 15 terms are:
1,11,2,10,20,3,4,100,5,6,7,200,8,9,13
Their successive digits are:
1,1,1,2,1,0,2,0,3,4,1,0,0,5,6,7,2,0,0,8,9,1,3
The prime rank digits are here (between parentheses):
1,(1)(1),2,(1)0,(2)0,3,4,(1)0(0),5,6,7,(2)0(0),8,9,1(3),...
Erasing the digits not in the parentheses:
.,(1)(1),.,(1).,(2).,.,.,(1).(0),.,.,.,(2).(0),.,.,.(3),...
The surviving digits are:
1,1,1,2,1,0,2,0,3,...
Those are indeed the digits of the starting sequence.


CROSSREFS

Sequence in context: A107831 A064928 A074335 * A273877 A066795 A079366
Adjacent sequences: A284209 A284210 A284211 * A284213 A284214 A284215


KEYWORD

nonn,base


AUTHOR

Eric Angelini and JeanMarc Falcoz, Mar 23 2017


STATUS

approved



