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A260312 Palindromic beastly primes that begin and end with digit '1'. 1
16661, 1000000000000066600000000000001, 10000000000000000000000000000000000000000006660000000000000000000000000000000000000000001 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The next term a(4) contains 1017 digits, and is too large to include in data section.

LINKS

Table of n, a(n) for n=1..3.

EXAMPLE

a(1) = 16661 is a palindromic prime that contains the beastly number '666' and begins and ends with digit 1.

a(2) = 1000000000000066600000000000001 is palindromic prime that contains the beastly number '666' and begins and ends with digit 1.

MAPLE

A260312:= n-> ((1*10^(n + 2) + 666)*10^n + 1 ): select(isprime, [seq((A260312 (n), n=1..100))]);

MATHEMATICA

Select[Table[(1*10^(n + 2) + 666)*10^n + 1, {n, 1000}], PrimeQ]

Select[Table[FromDigits[Join[{1}, PadRight[{}, n, 0], {6, 6, 6}, PadRight[ {}, n, 0], {1}]], {n, 0, 50}], PrimeQ] (* Harvey P. Dale, Jul 09 2017 *)

PROG

(PARI) for(n=1, 500, k=((1*10^(n + 2) + 666)*10^n + 1 ); if(isprime(k), print1(k, ", ")));

(MAGMA)  [k: n in [1..1000] | IsPrime(k) where k is ((1*10^(n + 2) + 666)*10^n + 1 )];

CROSSREFS

Cf. A046720, A051003, A131645, A186086.

Sequence in context: A196023 A108843 A232449 * A224572 A186311 A181098

Adjacent sequences:  A260309 A260310 A260311 * A260313 A260314 A260315

KEYWORD

nonn,base,less

AUTHOR

K. D. Bajpai, Jul 22 2015

STATUS

approved

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Last modified August 19 01:14 EDT 2017. Contains 290784 sequences.