A278649 Lexicographically earliest sequence of distinct terms such that, for any n>0, a(n+1) has a digit that divides a(n) and a(n) has a digit that divides a(n+1).

1, 10, 2, 12, 3, 15, 5, 25, 14, 7, 21, 11, 13, 16, 4, 20, 18, 6, 24, 8, 32, 22, 26, 28, 34, 27, 30, 33, 36, 9, 63, 39, 51, 17, 19, 31, 41, 61, 71, 81, 23, 100, 29, 102, 35, 45, 50, 55, 65, 54, 52, 40, 44, 48, 56, 42, 38, 72, 46, 92, 62, 82, 104, 43, 105, 37

Offset: 1

Author

Rémy Sigrist, Nov 25 2016

Keywords

• nonn
• base

Comments

This sequence combines the constraints met in A218468 and in A257277.

Links

• Rémy Sigrist, Table of n, a(n) for n = 1..10000
• Rémy Sigrist, PARI program for A278649

Crossrefs

Cf. A218468, A257277.

Programs

Mathematica

a = {1}; Do[k = 2; While[Or[Nand[AnyTrue[#2, Divisible[a[[n - 1]], #] &],
AnyTrue[#1, Divisible[k, #] &]], MemberQ[a, k]] & @@ Map[DeleteCases[ IntegerDigits@ #, 0] &, {a[[n - 1]], k}], k++]; AppendTo[a, k], {n, 2, 66}]; a (* Michael De Vlieger, Nov 25 2016, Version 10 *)