A120215 Start with 1057 and repeatedly reverse the digits and add 2 to get the next term.

1057, 7503, 3059, 9505, 5061, 1607, 7063, 3609, 9065, 5611, 1167, 7613, 3169, 9615, 5171, 1717, 7173, 3719, 9175, 5721, 1277, 7723, 3279, 9725, 5281, 1827, 7283, 3829, 9285, 5831, 1387, 7833, 3389, 9835, 5391, 1937, 7393, 3939, 9395, 5941, 1497, 7943, 3499, 9945, 5501

Offset: 1

Author

Klaus Brockhaus, Jun 11 2006

Keywords

• nonn
• base

Comments

Let T(S,Q) be the sequence obtained by starting with S and repeatedly reversing the digits and adding Q to get the next term. This is T(1057,2). 1057 is the first S for which T(S,2) reaches a cycle of length 45. The cycle is simply the first 45 terms, which then repeat. A full period is shown.

Links

• N. J. A. Sloane and others, Sequences of RADD type, OEIS wiki.
• Index entries for linear recurrences with constant coefficients, signature (0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1).

Crossrefs

Cf. A117521, A118514, A120214, A120216, A120217, A120218.

Programs

Mathematica

NestList[IntegerReverse[#]+2&,1057,50] (* Harvey P. Dale, Jan 25 2021 *)

Formula

a(n) = a(n-45). - Boštjan Gec, Sep 21 2023