A333480 Lexicographically earliest sequence of distinct positive integers such that the decimal expansions of neither a(n)/a(n+1) nor a(n+1)/a(n) contains a significant digit present in either a(n) or a(n+1).

2, 3, 5, 6, 8, 4, 11, 40, 12, 400, 22, 24, 72, 44, 36, 9, 18, 48, 16, 80, 33, 37, 45, 15, 50, 30, 20, 60, 54, 66, 55, 82, 75, 25, 220, 32, 288, 96, 396, 88, 64, 192, 576, 640, 480, 144, 4000, 110, 41, 148, 74, 90, 27, 81, 165, 495, 297, 99, 198, 540, 150, 444, 364, 2002, 224, 42, 7, 14, 70, 21

Offset

1,1

Comments

By "significant digit" we mean to exclude from the quotients any zeros preceding the first nonzero digit, as well as zeros following the last nonzero digit (as in a terminating decimal).

Is the sequence infinite?

Links

Table of n, a(n) for n=1..70.

Example

a(1)/a(2) = 2/3 = 0.666... and a(2)/a(1) = 3/2 = 1.5 and their combined distinct significant digits (1,5,6) are exclusive of the combined distinct digits of a(1) and a(2), (2,3).
a(7)/a(8) = 11/40 = 0.275 and a(8)/a(7) = 40/11 = 3.636363... and their combined distinct significant digits (2,3,5,6,7) are exclusive of the combined distinct digits of a(7) and a(8), (0,1,4).
a(106)/a(107) = 624/208 = 3 and a(107)/a(106) = 208/624 = 0.333... and their combined distinct significant digits (3) is exclusive of the combined distinct digits of a(106) and a(107), (0,2,4,6,8).

Crossrefs

Sequence in context: A357132 A067183 A269670 * A036587 A075145 A086142

Adjacent sequences: A333477 A333478 A333479 * A333481 A333482 A333483

Keyword

nonn,base

Author

Eric Angelini and Hans Havermann, Mar 23 2020

Status

approved