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A199328 Palindromic primes in the sense of A007500 with digits '0', '1' and '8' only. 2
11, 101, 181, 1181, 1811, 18181, 108881, 110881, 118081, 180181, 180811, 181081, 188011, 188801, 1008001, 1088081, 1110881, 1180811, 1181881, 1808801, 1880111, 1880881, 1881811, 1881881, 10001081, 10001801, 10011101, 10080011, 10101181, 10111001, 10111081, 10180801, 10188811, 10808101, 10810001 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Intersection of A007500 and A061247.

LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..4188

PROG

(PARI) a(n=50, L=[0, 1, 8], show=0)={my(t); for(d=1, 1e9, u=vector(d, i, 10^(d-i))~; forvec(v=vector(d, i, [1+(i==1&!L[1]), #L]), isprime(t=vector(d, i, L[v[i]])*u)|next; isprime(A004086(t))|next; show&print1(t", "); n--|return(t)))}

(Python)

from itertools import product

from sympy import isprime

A199328_list = [n for n in (int(''.join(s)) for s in product('018', repeat=10)) if isprime(n) and isprime(int(str(n)[::-1]))] # Chai Wah Wu, Dec 17 2015

CROSSREFS

Cf. A020449 - A020472, A199325 - A199329.

Sequence in context: A083185 A007597 A061247 * A068188 A032592 A180404

Adjacent sequences:  A199325 A199326 A199327 * A199329 A199330 A199331

KEYWORD

nonn,base

AUTHOR

M. F. Hasler, Nov 05 2011

STATUS

approved

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Last modified September 22 03:54 EDT 2020. Contains 337289 sequences. (Running on oeis4.)