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A262627 Minimal nested base-2 palindromic primes with seed 0. 19
0, 101, 11001010011, 101100101001101, 10101011001010011010101, 111010101100101001101010111, 1111101010110010100110101011111, 101111111010101100101001101010111111101, 110101111111010101100101001101010111111101011 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Using only base-2 digits 0 and 1, let s be a palindrome and put a(1) = s. Let a(2) be the least palindromic prime having s in the middle; for n > 2, let a(n) be the least palindromic prime have a(n-1) in the middle. Then (a(n)) is the sequence of minimal nested base-2 palindromic primes with seed s -- a(1) being not prime, of course.
Guide to related sequences
base seed base-b repr. base-10 repr.
LINKS
EXAMPLE
a(3) = 11001010011 =A117697(15) is the least prime having a(2) = 101 in its middle. Triangular format:
0
101
11001010011
101100101001101
10101011001010011010101
111010101100101001101010111
1111101010110010100110101011111
MATHEMATICA
s = {0}; base = 2; z = 20; Do[NestWhile[# + 1 &, 1, ! PrimeQ[tmp = FromDigits[Join[#, IntegerDigits[Last[s]], Reverse[#]] &[IntegerDigits[#, base]], base]] &];
AppendTo[s, FromDigits[IntegerDigits[tmp, base]]], {z}]; s (* A262627 *)
Map[FromDigits[ToString[#], base] &, s] (* A262628 *)
(* Peter J. C. Moses, Sep 01 2015 *)
CROSSREFS
Cf. A117697, A261881 (base 10), A262628-A262662.
Sequence in context: A138826 A292686 A138720 * A259199 A006064 A230304
KEYWORD
nonn,base
AUTHOR
Clark Kimberling, Oct 02 2015
STATUS
approved

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Last modified May 15 01:31 EDT 2024. Contains 372536 sequences. (Running on oeis4.)