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A048895 Bemirps: primes that yield a different prime when turned upside down with reversals of both being two more different primes. 17
1061, 1091, 1601, 1901, 10061, 10091, 16001, 19001, 106861, 109891, 168601, 198901, 1106881, 1109881, 1606081, 1806061, 1809091, 1886011, 1889011, 1909081, 10806881, 10809881, 11061811, 11091811, 11609681, 11698691, 11816011, 11819011, 11906981 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Emirps that yield other emirps when turned upside down. [Lekraj Beedassy, Apr 03 2009]

Invertible primes whose reversals are also invertible primes. [Lekraj Beedassy, Apr 04 2009]

All terms must begin and end with a one. - T. D. Noe, Apr 21 2014

LINKS

T. D. Noe, Table of n, a(n) for n = 1..468 (terms < 2 * 10^9)

MATHEMATICA

upDown[0] = 0; upDown[1] = 1; upDown[6] = 9; upDown[8] = 8; upDown[9] = 6; fQ[p_] := Module[{revP, upDownP, revUpDownP}, If[Intersection[{2, 3, 4, 5, 7}, Union[IntegerDigits[p]]] != {}, False, revP = FromDigits[Reverse[IntegerDigits[p]]]; upDownP = FromDigits[upDown /@ IntegerDigits[p]]; revUpDownP = FromDigits[Reverse[IntegerDigits[upDownP]]]; p != revP && p != upDownP && p != revUpDownP && PrimeQ[revP] && PrimeQ[upDownP] && PrimeQ[revUpDownP]]]; t = {}; nn = 6; Do[p = 10^n; While[p < 2*10^n, p = NextPrime[p]; If[fQ[p], AppendTo[t, p]]], {n, nn}]; t (* T. D. Noe, Apr 21 2014 *)

CROSSREFS

Cf. A003684, A006567, A007628, A046732, A048051, A048052, A048053, A048054.

Sequence in context: A107556 A237797 A237795 * A020374 A142822 A172384

Adjacent sequences:  A048892 A048893 A048894 * A048896 A048897 A048898

KEYWORD

base,nonn,nice,changed

AUTHOR

G. L. Honaker, Jr.

EXTENSIONS

More terms from David W. Wilson.

STATUS

approved

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Last modified April 23 11:03 EDT 2014. Contains 240919 sequences.