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A241096 Palindromes in base 16 whose squares are also palindromes. 1
1, 2, 3, 11, 22, 101, 111, 121, 131, 202, 212, 222, 1001, 1111, 1221, 2002, 2112, 10001, 10101, 10201, 10301, 11011, 11111, 11211, 11311, 12021, 12121, 12221, 20002, 20102, 20202, 21012, 21112, 21212, 100001, 101101, 102201, 110011, 111111, 112211, 120021 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Lars Blomberg, Table of n, a(n) for n = 1..10000

EXAMPLE

131 qualifies for this sequence because (unlike in base 10, where squaring 131 carries a 1 into the thousands place so that 131^2 is the non-palindromic number 17161) in base 16, 131^2 is 16B61. 141 doesn't qualify because, even in base 16, a 1 is carried into the next place, so the result (19281) is not palindromic.

PROG

(Sage)

L=[]

for x in [1..100000]:

    M=x.digits(base=16)

    N=M[::-1]

    if N == M:

        d=x^2

        D=d.digits(base=16)

        E=D[::-1]

        if D == E:

            MM=(str(x) for x in M)

            L.append(Integer(''.join(MM)))

L # Tom Edgar, Apr 29 2014

CROSSREFS

Cf. A057135.

Sequence in context: A118595 A229549 A229804 * A057135 A229805 A104075

Adjacent sequences:  A241093 A241094 A241095 * A241097 A241098 A241099

KEYWORD

nonn,base

AUTHOR

J. Lowell, Apr 26 2014

EXTENSIONS

a(35)-a(41) from Lars Blomberg, Oct 23 2014

STATUS

approved

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Last modified October 26 20:19 EDT 2021. Contains 348269 sequences. (Running on oeis4.)