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A115761
Numbers k such that the digits of k^2, reversed, include the digits of k as a substring.
6
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.
Sequence in context: A303731 A298175 A298144 * A320047 A249221 A127040
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