A334737 Lexicographically earliest sequence of distinct positive integers such that the digital root of a(n+1) divides a(n).

1, 10, 2, 11, 19, 28, 4, 13, 37, 46, 20, 5, 14, 7, 16, 8, 17, 55, 23, 64, 22, 29, 73, 82, 38, 47, 91, 25, 32, 26, 56, 31, 100, 40, 35, 34, 65, 41, 109, 118, 74, 83, 127, 136, 44, 49, 43, 145, 50, 59, 154, 52, 58, 92, 67, 163, 172, 76, 85, 68, 94, 101, 181, 190, 77, 61, 199

Offset

1,2

Links

Carole Dubois, Table of n, a(n) for n = 1..5005

Example

a(1) = 1 is divisible by the digital root of 10 (which is 1 + 0 = 1);
a(2) = 10 is divisible by the dig. root of 2 (which is = 2);
a(3) = 2 is divisible by the dig. root of 11 (which is 1 + 1 = 2);
a(4) = 11 is divisible by the dig. root of 19 (which is 1 + 9 = 10 => 1 + 0 = 1);
a(5) = 19 is divisible by the dig. root of 28 (which is 2 + 8 = 10 => 1 + 0 = 1);
a(6) = 28 is divisible by the dig. root of 4 (which is = 4); etc.

Crossrefs

Cf. A248025, A334837 (same idea, but digital sum instead of digital root in the Name section).

Sequence in context: A257277 A248024 A269631 * A334837 A327689 A317387

Adjacent sequences: A334734 A334735 A334736 * A334738 A334739 A334740

Keyword

base,nonn

Author

Eric Angelini and Carole Dubois, May 09 2020

Status

approved