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A153806 Strobogrammatic cyclops numbers. 8
0, 101, 609, 808, 906, 11011, 16091, 18081, 19061, 61019, 66099, 68089, 69069, 81018, 86098, 88088, 89068, 91016, 96096, 98086, 99066, 1110111, 1160911, 1180811, 1190611, 1610191, 1660991, 1680891, 1690691, 1810181, 1860981 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Intersection of A000787 and A134808.

LINKS

Kenny Lau, Table of n, a(n) for n = 1..20000

EXAMPLE

1680891 is a member because it is the same upside down (A000787) and also a cyclops number (A134808).

MATHEMATICA

Select[Range[10^7], And[OddQ@ Length@#, Part[#, Ceiling[Length[#]/2]] == 0, Times @@ Boole@ Map[MemberQ[{0, 1, 6, 8, 9}, #] &, Union@ #] == 1, Count[#, 0] == 1, (Take[#, Floor[Length[#]/2]] /. {6 -> 9, 9 -> 6}) ==

Reverse@ Take[#, -Floor[Length[#]/2]]] &@ IntegerDigits@ # &] (* Michael De Vlieger, Jul 05 2016 *)

PROG

(Python)

import sys

f = open('b153806.txt', 'w')

i = 1

n = 0

a = [""]

r = [""]  #reversed strobogrammatically

while True:

....for x, y in zip(a, r):

........f.write(str(i)+" "+x+"0"+y+"\n")

........i += 1

........if i>20000:

............f.close()

............sys.exit()

....a = sum([[x+"1", x+"6", x+"8", x+"9"] for x in a], [])

....r = sum([["1"+x, "9"+x, "8"+x, "6"+x] for x in r], [])

# Kenny Lau, Jul 05 2016

CROSSREFS

Cf. A000787, A007597, A134808, A134809, A138131, A138148, A153807.

Sequence in context: A060012 A142507 A131697 * A227521 A171813 A089291

Adjacent sequences:  A153803 A153804 A153805 * A153807 A153808 A153809

KEYWORD

base,easy,nonn

AUTHOR

Omar E. Pol, Jan 15 2009

EXTENSIONS

Extended beyond 11011 by R. J. Mathar, Jan 17 2009

STATUS

approved

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Last modified July 21 02:53 EDT 2017. Contains 289629 sequences.