A115761 Numbers k such that the digits of k^2, reversed, include the digits of k as a substring.

1, 5, 6, 27, 74, 963, 5723, 6142, 6524, 9867, 53152, 65766, 69714, 351732, 409761, 497674, 624279, 664902, 697140, 781101, 2733747, 3879405, 4897317, 5031485, 6317056, 6971400, 8403702, 9324454, 16013465, 21646858, 34679962, 36909226, 38794051, 40781862, 41065012

Offset

1,2

Links

Giovanni Resta, Table of n, a(n) for n = 1..97 (terms < 4*10^12)

Example

963^2 = 927(369).

Mathematica

fQ[n_] := StringPosition[ IntegerString[n^2], StringReverse@ IntegerString@n] != {}; k = 1; lst = {}; While[k < 38794050, If[ fQ@k, AppendTo[lst, k]]; k++ ]; lst (* Robert G. Wilson v, Jul 28 2010 *)
Select[Range[37*10^6], SequenceCount[Reverse[IntegerDigits[#^2]], IntegerDigits[ #]]>0&] (* The program uses the SequenceCount function from Mathematica version 10 *) (* Harvey P. Dale, May 02 2016 *)

Crossrefs

Contains A269588 as a subsequence.

Cf. A115762, A115763, A115764, A115738, A179803.

Sequence in context: A303731 A298175 A298144 * A320047 A249221 A127040

Adjacent sequences: A115758 A115759 A115760 * A115762 A115763 A115764

Keyword

nonn,base

Author

Giovanni Resta, Jan 30 2006

Extensions

More terms from Robert G. Wilson v, Jul 28 2010

Terms a(33) and beyond from Giovanni Resta, May 04 2020

Status

approved