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A029990
Numbers k such that k^2 is palindromic in base 6.
13
0, 1, 2, 7, 37, 43, 76, 91, 217, 259, 1064, 1297, 1333, 1519, 1555, 2704, 3367, 7777, 8029, 9079, 19747, 46657, 46873, 47989, 48205, 54439, 54655, 54695, 83979, 118027, 241304, 279937, 281449, 287749, 326599, 707707, 1679617
OFFSET
1,3
LINKS
Patrick De Geest, Palindromic Squares
MATHEMATICA
palindromicQ[n_, b_:10] := TrueQ[IntegerDigits[n, b] == Reverse[IntegerDigits[n, b]]]; Select[Range[1000], palindromicQ[#^2, 6] &] (* Alonso del Arte, Mar 05 2017 *)
PROG
(PARI) ispal(n, base)=my(d=digits(n, base)); d==Vecrev(d)
is(n)==ispal(n^2, 6) \\ Charles R Greathouse IV, Mar 09 2017
CROSSREFS
Cf. A007092.
Numbers k such that k^2 is palindromic in base b: A003166 (b=2), A029984 (b=3), A029986 (b=4), A029988 (b=5), this sequence (b=6), A029992 (b=7), A029805 (b=8), A029994 (b=9), A002778 (b=10), A029996 (b=11), A029737 (b=12), A029998 (b=13), A030072 (b=14), A030073 (b=15), A029733 (b=16), A118651 (b=17).
Sequence in context: A368398 A274904 A173827 * A042465 A041051 A175487
KEYWORD
nonn,base
STATUS
approved