

A220121


Corresponding to the bases in A220120, the smallest primes such that there are two smaller that juxtaposed with it all 6 ways produces primes.


1



83, 97, 103, 137, 149, 181, 199, 277, 281, 389, 431, 541, 557, 617, 733, 967, 1049, 1061, 1619
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OFFSET

1,1


COMMENTS

The (or one of the) pair(s) that are companion to the primes of this sequence are {5,37}, {11,41}, {23,37}, {23,67}, {37,79}, {41,131}, {37,101}, {107,199}, {241,277}, {151,199}, {79,109}, {311,409}, {257,283}, {241,317}, {223,443}, {29,293}, {23,569}, {53,383} and {509,1433}.


LINKS

Table of n, a(n) for n=1..19.


EXAMPLE

In binary (base 2), any triple of primes under 83 contains a composite among its 6 possible orders of juxtaposition. Decimal {5,37,83} corresponds to binary {101, 100101, 1010011} and the 6 binary juxtapositions {1001011010011101, 1001011011010011, 1010011100101101, 1010011101100101, 1011001011010011, 1011010011100101}  {38557, 38609, 42797, 42853, 45779, 46309} in decimal  are all prime. So, a(1)=83.


CROSSREFS

Cf. A220120.
Sequence in context: A284292 A045714 A090156 * A335916 A158719 A160028
Adjacent sequences: A220118 A220119 A220120 * A220122 A220123 A220124


KEYWORD

nonn,base


AUTHOR

James G. Merickel, Dec 05 2012


STATUS

approved



