

A306311


Lexicographically earliest sequence starting with a(1) = 1 with no duplicate terms such that the nth digit of the sequence is a divisor of a(n).


7



1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, 15, 18, 16, 24, 17, 25, 19, 32, 21, 36, 22, 28, 23, 35, 26, 45, 27, 54, 33, 34, 38, 29, 39, 42, 44, 46, 48, 56, 52, 51, 57, 55, 58, 66, 64, 65, 62, 49, 75, 68, 63, 69, 72, 76, 78, 88, 74, 81, 84, 99, 92, 82, 96, 112, 116, 114, 124, 128, 85, 126, 95, 86, 115, 31, 125, 77, 135, 145, 155
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,2


COMMENTS

This sequence is a derangement of the zeroless numbers; any 0 digit in a(n) would force a division by zero later in the sequence.


LINKS

JeanMarc Falcoz, Table of n, a(n) for n = 1..20010


EXAMPLE

The sequence starts with 1,2,3,4,5,6,7,8,9,11,12,13,14,15,18,16,24,17,25,19,32,21,...
The first nine terms speak for themselves;
the 10th digit of the sequence is 1 and 1 is a divisor of a(10) = 11;
the 11th digit of the sequence is 1 and 1 is a divisor of a(11) = 12;
the 12th digit of the sequence is 1 and 1 is a divisor of a(12) = 13;
the 13th digit of the sequence is 2 and 2 is a divisor of a(13) = 14;
the 14th digit of the sequence is 1 and 1 is a divisor of a(14) = 15;
the 15th digit of the sequence is 3 and 3 is a divisor of a(15) = 18;
etc.


CROSSREFS

Cf. A052382 (the zeroless numbers).
Sequence in context: A052044 A253643 A050743 * A028964 A219361 A191878
Adjacent sequences: A306308 A306309 A306310 * A306312 A306313 A306314


KEYWORD

base,nonn


AUTHOR

Eric Angelini and JeanMarc Falcoz, Feb 06 2019


STATUS

approved



