A289288 Starting with a(1) = 1, a(n) = smallest nonnegative integer not yet in the sequence such that the last digit of a(n-1) plus the first digit of a(n) is equal to 10. The digit 0 is not allowed.

1, 9, 11, 91, 92, 8, 2, 81, 93, 7, 3, 71, 94, 6, 4, 61, 95, 5, 51, 96, 41, 97, 31, 98, 21, 99, 12, 82, 83, 72, 84, 62, 85, 52, 86, 42, 87, 32, 88, 22, 89, 13, 73, 74, 63, 75, 53, 76, 43, 77, 33, 78, 23, 79, 14, 64, 65, 54, 66, 44, 67, 34, 68, 24, 69, 15, 55, 56, 45, 57, 35, 58, 25, 59, 16, 46, 47, 36, 48, 26, 49, 17, 37, 38, 27, 39, 18, 28, 29, 19, 111, 911, 912, 811, 913, 711, 914, 611, 915, 511, 916, 411, 917, 311, 918, 211, 919, 112, 812, 813, 712

Offset: 1

Author

Enrique Navarrete, Jul 01 2017

Keywords

• nonn
• base

Comments

Unlike the sequences in A289283 - A289287, this sequence is infinite and does not seem to follow central polygonal numbers.

Crossrefs

Cf. A002061, A289283, A289284, A289285, A289286, A289287.

Programs

Mathematica

Module[{a = {1}, k, d = 10}, TimeConstrained[Do[k = 2; While[Or[MemberQ[a, k], MemberQ[IntegerDigits@ k, 0], # != d] &[Mod[a[[n - 1]], 10] + First@ IntegerDigits@ k], k++]; AppendTo[a, k], {n, 2, Infinity}], 2]; a] (* Michael De Vlieger, Jul 14 2017 *)