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A278696
Primes p such that every suffix of the ternary (base-3) representation of p is a prime.
1
2, 5, 11, 23, 29, 59, 83, 167, 173, 191, 491, 509, 569, 653, 659, 677, 1481, 1487, 1949, 2027, 2111, 4397, 4457, 4547, 4943, 5051, 5861, 6323, 6563, 13127, 13151, 13313, 13613, 13691, 13781, 13799, 15149, 15233, 17519, 17579, 17669, 39371, 39857, 40847, 40853, 43913, 44417, 52517, 53147, 59051
OFFSET
1,1
COMMENTS
All numbers in the sequence are of one of the forms, base 3:
a. 2
b. 10...02, where there are 0 or more 0's
c. 20...0x, where there are 0 or more 0's, and x is of the form b or c
There is always exactly one 1 in the number, base 3.
All numbers end in a 2, base 3.
LINKS
EXAMPLE
569 is in the sequence, as 569=210002_3 and its base-3 suffixes are 10002_3=83 and 2_3=2, both of which are prime.
MAPLE
F[1]:= [2]:
for m from 2 to 11 do
F[m]:= [op(F[m-1]), op(select(isprime, [seq(seq(i*3^
(m-1)+x, x=F[m-1]), i=[1, 2])]))]
od:
F[11]; # Robert Israel, Jan 22 2020
CROSSREFS
Cf. A278694.
Sequence in context: A180337 A257130 A038924 * A226843 A057931 A039693
KEYWORD
nonn,base
AUTHOR
Randy L. Ekl, Nov 26 2016
STATUS
approved