A089183 Palindromes in which, in the first half of the number, digits appear in the order 1, 0, 2, 3, 1, 0, 2, 3, 1, ...

1, 11, 101, 1001, 10201, 102201, 1023201, 10233201, 102313201, 1023113201, 10231013201, 102310013201, 1023102013201, 10231022013201, 102310232013201, 1023102332013201, 10231023132013201, 102310231132013201

Offset: 1

Author

Roger L. Bagula, Dec 07 2003

Keywords

• nonn
• base

Comments

A method of altering the order in the digit sets of palindromic numbers and making continued fractions from them.

Crossrefs

Cf. A007907.

Programs

Mathematica

digits=50 c={1, 0, 2, 3} a[m_]=Delete[Table[If [ Floor[m/2]-n>=0, c[[ Mod[n, 4]]], c[[Mod[m-n, 4]]]], {n, 1, m}], m] b=Table[Sum[a[m][[i]]*10^(i-1), {i, 1, m-1}], {m, 2, digits}]

Formula

c[1]=1 c[2]=0 c[3]=2 c[0]=3 a[m] = Delete[Table[If [ Floor[m/2]-n>=0, c[ Mod[n, 4]], c[Mod[m-n, 4]]], {n, 1, m}], m] b[m]=Sum[a[m][[i]]*10^(i-1), {i, 1, m-1}]

Extensions

Edited by N. J. A. Sloane, Jan 05 2009.