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A007597 Strobogrammatic primes.
(Formerly M4800)
13
11, 101, 181, 619, 16091, 18181, 19861, 61819, 116911, 119611, 160091, 169691, 191161, 196961, 686989, 688889, 1008001, 1068901, 1160911, 1180811, 1190611, 1191611, 1681891, 1690691, 1880881, 1881881, 1898681, 1908061, 1960961, 1990661 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Primes which are invariant under a 180 degree rotation.

REFERENCES

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

C. W. Trigg, "Strobogrammatic Primes and Prime Rotative Twins", J. Rec. Math., 15 (1983), 281-282.

LINKS

Table of n, a(n) for n=1..30.

C. K. Caldwell, The Prime Glossary, Strobogrammatic

Wikipedia, Strobogrammatic prime

MATHEMATICA

lst = {}; fQ[n_] := Block[{allset = {0, 1, 6, 8, 9}, id = IntegerDigits@n}, Union@ Join[id, allset] == allset && Reverse[id /. {6 -> 9, 9 -> 6}] == id]; Do[ If[ PrimeQ@n && fQ@n, AppendTo[lst, n]], {n, 2000000}]; lst (* Robert G. Wilson v, Feb 27 2007 *)

CROSSREFS

Cf. A000787.

Sequence in context: A089716 A084987 A083185 * A061247 A199328 A068188

Adjacent sequences:  A007594 A007595 A007596 * A007598 A007599 A007600

KEYWORD

base,nonn

AUTHOR

N. J. A. Sloane, Robert G. Wilson v

EXTENSIONS

More terms from David W. Wilson

STATUS

approved

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Last modified October 24 09:28 EDT 2014. Contains 248516 sequences.