OFFSET

2,1

COMMENTS

All terms in the palindromic part of the continued fraction expansion of sqrt(a(n)) are themselves palindromes. - Chai Wah Wu, Sep 15 2021

LINKS

Chai Wah Wu, Table of n, a(n) for n = 2..71 (terms n = 2..49 from Jon E. Schoenfield)

Jon E. Schoenfield, The continued fraction for each term up through a(49)

EXAMPLE

23 is in the sequence because it is the first, followed by 47, 96, 98, 119, 128, ... all exhibiting the following property: sqrt(23) = [4; 1, 3, 1, 8], sqrt(47) = [6; 1, 5, 1, 12], sqrt(96) = [9; 1, 3, 1, 18], sqrt(98) = [9; 1, 8, 1, 18], sqrt(119) = [10; 1, 9, 1, 20], sqrt(128) = [11; 3, 5, 3, 22], ... i.e., the continued fraction expansion of their square roots have palindrome parts which concatenate respectively to the 3-digit palprimes 131, 151, 131, 181, 191, 353, ...

CROSSREFS

KEYWORD

hard,nice,nonn,base

AUTHOR

Lekraj Beedassy, Jun 26 2002

EXTENSIONS

a(5)-a(36) from Jon E. Schoenfield, Apr 02 2010

STATUS

approved