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A068188 Tetradic primes (primes in A006072). 5
11, 101, 181, 18181, 1008001, 1180811, 1880881, 1881881, 100111001, 100888001, 108101801, 110111011, 111010111, 111181111, 118818811, 180101081, 181111181, 181888181, 188010881, 188888881, 10008180001, 10081818001 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Primes that are palindromes and use only the digits 0, 1 and 8, so they read the same backwards and upside down.

LINKS

Table of n, a(n) for n=1..22.

Eric Weisstein's World of Mathematics, Tetradic Number

MATHEMATICA

TetrPrmsUpTo10powerK[k_]:= Select[FromDigits/@ Tuples[{0, 1, 8}, k],

PrimeQ[#] && IntegerDigits[#] == Reverse[IntegerDigits[#]] &]; TetrPrmsUpTo10powerK[13](* Mikk Heidemaa, May 20 2017 *)

CROSSREFS

Subsequence of A030430.

Sequence in context: A007597 A061247 A199328 * A032592 A180404 A142317

Adjacent sequences:  A068185 A068186 A068187 * A068189 A068190 A068191

KEYWORD

nonn,easy,base

AUTHOR

Eric W. Weisstein, Feb 18 2002

EXTENSIONS

Edited by Jud McCranie, Jun 02 2003

Offset corrected by Arkadiusz Wesolowski, Oct 17 2011

STATUS

approved

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Last modified November 20 12:20 EST 2017. Contains 294968 sequences.