login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 56th year, we are closing in on 350,000 sequences, and we’ve crossed 9,700 citations (which often say “discovered thanks to the OEIS”).

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A060087 Numbers n such that n^2 is a palindromic square with an asymmetric root. 3
1109111, 110091011, 111091111, 10109901101, 10110911101, 11000910011, 11010911011, 11100910111, 1010099010101, 1010109110101, 1011099011101, 1100009100011, 1101009101011, 1110009100111, 100109990011001 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

With 'asymmetric' is meant almost palindromic with a 'core' (pseudo-palindromic). The core '09' when transformed into '1n' (n=-1) makes the base number palindromic. E.g., 1109111 is in fact 11_09_111 -> 11_(10-1)_111 -> 11_1n_111 -> 111n111 and palindromic. Similarly core 099 becomes 10n, core 0999 becomes 100n, etc.

REFERENCES

M. Keith, "Classification and Enumeration of Palindromic Squares," Journal of Recreational Mathematics, 22:2, pp. 124-132, 1990.

LINKS

Table of n, a(n) for n=1..15.

P. De Geest, Subsets of Palindromic Squares

CROSSREFS

Cf. A060088, A007573, A059744, A059745.

Sequence in context: A316481 A253619 A235221 * A229783 A176999 A035613

Adjacent sequences:  A060084 A060085 A060086 * A060088 A060089 A060090

KEYWORD

nonn,base

AUTHOR

Patrick De Geest, Feb 15 2001

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 4 04:49 EST 2021. Contains 349469 sequences. (Running on oeis4.)