A135699 Palindromes with odd number of digits formed from the reflected decimal expansion of golden ratio phi.

1, 161, 16161, 1618161, 161808161, 16180308161, 1618033308161, 161803393308161, 16180339893308161, 1618033988893308161, 161803398878893308161, 16180339887478893308161

Offset: 1

Author

Omar E. Pol, Mar 01 2008

Keywords

• base
• nonn

Comments

Phi = 1.61803398874989484820458683436... (see A001622).

The number of digits of a(n) is equal to 2n - 1.

Examples

			n ............ a(n)
1 ............. 1
2 ............ 161
3 ........... 16161
4 .......... 1618161
5 ......... 161808161
6 ........ 16180308161
7 ....... 1618033308161
8 ...... 161803393308161
9 ..... 16180339893308161
10 ... 1618033988893308161
		

Links

• G. C. Greubel, Table of n, a(n) for n = 1..250

Crossrefs

Cf. A001622, A002113.

Programs

Mathematica

With[{ed = RealDigits[(1 + Sqrt[5])/2, 10, 25][[1]]}, Table[FromDigits[Join[Take[ed, n], Reverse[Take[ed, n - 1]]]], {n,25}]] (* G. C. Greubel, Oct 27 2016 *)