A050741 Numbers k such that the decimal expansion of k^2 contains no pair of consecutive equal digits.

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 13, 14, 16, 17, 18, 19, 22, 23, 24, 25, 26, 27, 28, 29, 31, 32, 33, 36, 37, 39, 41, 42, 43, 44, 45, 48, 49, 51, 52, 53, 54, 55, 56, 57, 59, 61, 63, 64, 66, 68, 69, 71, 72, 73, 74, 75, 77, 78, 79, 81, 82, 84, 86, 87, 89, 91, 92, 93, 95, 96, 97

Offset

1,3

Links

Zak Seidov and Michael De Vlieger, Table of n, a(n) for n = 1..10471, a(n) < 25,000 (First 1057 terms from Zak Seidov)

Example

10 is absent because 10^2=100 with repeating 0,
12 is absent because 12^2=144 with repeating 4,
21 is absent because 21^2=441 with repeating 4.

Mathematica

Select[Range[0, 97], FreeQ[Differences[IntegerDigits[#^2]], 0]&] (* Jayanta Basu, May 31 2013 *)

Crossrefs

Cf. A043096, A050749, A135463, A134962.

Sequence in context: A191841 A331125 A318736 * A285710 A305669 A325364

Adjacent sequences: A050738 A050739 A050740 * A050742 A050743 A050744

Keyword

nonn,base

Author

Patrick De Geest, Sep 15 1999

Extensions

Edited by N. J. A. Sloane, Mar 16 2008

Status

approved