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A018846 Strobogrammatic numbers: numbers that are the same upside down (using calculator-style numerals). 9

%I

%S 0,1,2,5,8,11,22,55,69,88,96,101,111,121,151,181,202,212,222,252,282,

%T 505,515,525,555,585,609,619,629,659,689,808,818,828,858,888,906,916,

%U 926,956,986,1001,1111,1221,1551,1691,1881,1961,2002,2112,2222,2552,2692,2882

%N Strobogrammatic numbers: numbers that are the same upside down (using calculator-style numerals).

%C A018847 lists primes in this sequence. - _M. F. Hasler_, May 05 2012

%H T. D. Noe, <a href="/A018846/b018846.txt">Table of n, a(n) for n=1..1000</a>

%o (PARI) is_A018846(n,t=Vec("012..59.86"))={ apply(x->t[eval(x)+1], n=Vec(Str(n)))==vecextract(n, "-1..1") } \\ - _M. F. Hasler_, May 05 2012

%Y Cf. A053701 (vertically symmetric numbers), A048708.

%K nonn,base,easy,nice

%O 1,3

%A _David W. Wilson_

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Last modified November 20 10:09 EST 2019. Contains 329334 sequences. (Running on oeis4.)