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A275028 Square numbers with the property that their digital rotation is still a square number. 0
1, 121, 196, 529, 625, 961, 6889, 10201, 69169, 1002001, 1022121, 1212201, 5221225, 100020001, 100220121, 109181601, 121022001, 522808225, 602555209, 10000200001, 10002200121, 10020210201, 10201202001, 12100220001, 62188888129, 1000002000001 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

From Jon E. Schoenfield, Nov 13 2016: (Start)

It is assumed that the rotation changes each digit 6 to a 9 and vice versa, and that the digits 0, 1, 2, 5, and 8 are unchanged by the rotation, as is the case with a seven-segment display in which the digits are formed basically as follows:

.    _       _   _         _    _   _    _    _

    | |  |   _|  _|  |_|  |_   |_    |  |_|  |_|

    |_|  |  |_   _|    |   _|  |_|   |  |_|   _|

(End)

LINKS

Table of n, a(n) for n=1..26.

Prime Curios, 31

EXAMPLE

For example, 961 becomes 196 under such a rotation.

MATHEMATICA

Select[Range[10^6]^2, If[Or[IntersectingQ[#, {3, 4, 7}], Last@# == 0], False, IntegerQ@ Sqrt@ FromDigits[Reverse@ # /. {6 -> 9, 9 -> 6}]] &@ IntegerDigits@ # &] (* Michael De Vlieger, Nov 14 2016 *)

CROSSREFS

Cf. A178316.

Sequence in context: A074730 A268519 A037050 * A036309 A346507 A119378

Adjacent sequences:  A275025 A275026 A275027 * A275029 A275030 A275031

KEYWORD

nonn,base

AUTHOR

Seiichi Manyama, Nov 12 2016

STATUS

approved

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Last modified August 1 08:54 EDT 2021. Contains 346385 sequences. (Running on oeis4.)