A140463 -id:A140463 - cp's OEIS frontend

A215649 Reversals of tribonacci numbers (sorted).

0, 0, 1, 1, 2, 4, 7, 18, 31, 42, 44, 405, 472, 729, 941, 5071, 6313, 8675, 9853, 21066, 31591, 90601, 447014, 514121, 674557, 713322, 770074, 4606468, 7359831, 7575552, 8089735, 19520951, 52494292, 69005989, 106799181, 474396516, 777547433, 2586342311, 3016782802

Offset: 0

Jonathan Vos Post, Mar 09 2013

This is to A004170 as tribonacci numbers A000073 are to Fibonacci numbers A000045. Note that tribonacci(20) = 35890 is, upon reversal, 09853, then the leading 0 is truncated, making the 5-digit number into the 4-digit number 9853. Similarly, R(4700770) = 770074.

			A000073(n) for n = 7, 8, 9 = 13, 24, 44, 81. Reversed, those are 31, 42, 44, 18, and sorted that is 18, 31, 42, 44.

Harvey P. Dale, Table of n, a(n) for n = 0..1000

Cf. A000045, A000073, A004086, A004170, A004091, A140463, A214855, A004086.

Sort[FromDigits[Reverse[IntegerDigits[#]]]&/@LinearRecurrence[{1,1,1},{0,0,1,1},40]] (* Harvey P. Dale, Nov 22 2015 *)

A267551 Lucas numbers written backwards.

Original entry on oeis.org

2, 1, 3, 4, 7, 11, 81, 92, 74, 67, 321, 991, 223, 125, 348, 4631, 7022, 1753, 8775, 9439, 72151, 67442, 30693, 97046, 286301, 167761, 344172, 402934, 746017, 1589411, 8940681, 9430103, 7480784, 6911887, 34025721, 93233602, 28258333, 12581045, 30830478

Offset: 0

Vincenzo Librandi, Jan 17 2016

			81 is in the sequence because 7 + 11 = 18, which is 81 written backwards.

Seiichi Manyama, Table of n, a(n) for n = 0..1000

Cf. A000032, A004086, A004091, A140463.

[Seqint(Reverse(Intseq(Lucas(n)))): n in [0..50]];

FromDigits[Reverse[IntegerDigits[#]]]&/@LucasL[Range[0, 50]]

a(n) = eval(concat(Vecrev(Str(fibonacci(n+1)+fibonacci(n-1))))); \\ Altug Alkan, Jan 17 2016

a(n) = A004086(A000032(n)).

cp's OEIS Frontend

A215649 Reversals of tribonacci numbers (sorted).

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