|
Search: id:A087532
|
|
|
| A087532 |
|
Primes consisting only of digits 3 and 8 occurring with equal frequency. |
|
+0
2
|
|
| 83, 38383883, 88838333, 3338388883, 3388338883, 3388833883, 3388838833, 3833388883, 3838383883, 3838388383, 3838838383, 3838883383, 3883883833, 8333888383, 8338383883, 8338888333, 8383338883, 8383388383, 8383888333
(list; graph; listen)
|
|
|
OFFSET
|
0,1
|
|
|
COMMENT
|
There are 18 digit pairs which can produce such primes. (1,0),(7,0),(1,3),(1,4),(1,6),(1,7),(1,9),(2,3),(2,9),(3,4),(3,5),(3,7),(3,8),(4,7),(4,9),(5,9),(6,7),(7,9).
|
|
MAPLE
|
Primes consisting only of digits x and y, occurring with equal frequency. PARI CODE: d1=x; d2=y; k=0; a=vector(100); for(n=1, 3000, B=binary(n); L=length(B); s=sum(j=1, length(B), B[j]); if(L%2==0 & s==L/2, C=vector(L, n, (d2-d1)*B[n]+d1); p=subst(Pol(C), x, 10); if(isprime(p), if(k<100, k++; a[k]=p)); D=vector(L, n, d2-(d2-d1)*B[n]); q=subst(Pol(D), x, 10); if(isprime(q ), if(k<100, k++; a[k]=q))); ); a=vector(k, n, a[n]); vecsort(a)
|
|
CROSSREFS
|
Cf. A087510, A087511, A087531.
Adjacent sequences: A087529 A087530 A087531 this_sequence A087533 A087534 A087535
Sequence in context: A097839 A087189 A116263 this_sequence A116307 A093676 A130432
|
|
KEYWORD
|
base,nonn
|
|
AUTHOR
|
Amarnath Murthy and Paul D. Hanna (pauldhanna(AT)juno.com) (amarnath_murthy(AT)yahoo.com), Sep 12 2003
|
|
|
Search completed in 0.002 seconds
|
