A284212 The successive digits of the sequence are the same digits that have a prime rank in the sequence.

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

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

Jean-Marc 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: A064928 A074335 A367812 * A273877 A066795 A079366

Adjacent sequences: A284209 A284210 A284211 * A284213 A284214 A284215

Keyword

nonn,base

Author

Eric Angelini and Jean-Marc Falcoz, Mar 23 2017

Status

approved