

A323783


a(n) = A134028(A323782(n)): Primes and negated primes such that the reverse of the balanced ternary representation is a prime.


1



2, 11, 7, 5, 13, 29, 17, 37, 31, 43, 83, 101, 61, 89, 73, 53, 71, 59, 103, 173, 313, 353, 241, 137, 263, 223, 331, 277, 181, 269, 163, 179, 233, 199, 347, 139, 193, 311, 149, 367, 853, 691, 929, 443, 983, 421, 389, 839, 457, 677
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OFFSET

1,1


COMMENTS

The "warp" operation is reversible between A323782 and this sequence.
Negating a number in balanced ternary notation is done by inverting the + and .


LINKS

Table of n, a(n) for n=1..50.
Github, Python code repository
Rosetta Code, Balanced Ternary Code
Wikipedia, Balanced Ternary


EXAMPLE

17 is a term:
17 is +0+ in balanced ternary notation
+0+ reversed is +0+
+0+ is 29 in balanced ternary notation
29 is prime
Therefore 17 is "warped" to 29.
This operation is reversible: 29 "warps" to 17.


PROG

(Python) See links
(PARI) d3(n) = if ((n%3)==2, n\3+1, n\3);
m3(n) = if ((n%3)==2, 1, n % 3);
t(n) = if (n==0, [0], if (abs(n) == 1, [n], concat(m3(n), t(d3(n)))));
f(n) = subst(Pol(Vec(t(n))), x, 3);
lista(nn) = {forprime(n=1, nn, if (isprime(abs(f(n))), print1(f(n), ", ")); ); } \\ Michel Marcus, Jan 29 2019


CROSSREFS

Corresponding warp prime numbers to A323782.
Supersequence of A224502.
Sequence in context: A226219 A285866 A165768 * A306537 A170873 A224210
Adjacent sequences: A323780 A323781 A323782 * A323784 A323786 A323787


KEYWORD

sign,base


AUTHOR

Philippe Cochin, Jan 27 2019


STATUS

approved



