A089758 Primes arising in A089757.

31, 631, 9631, 129631, 27129631, 3027129631, 393027129631, 42393027129631, 6642393027129631, 1626642393027129631, 2311626642393027129631, 2522311626642393027129631, 2582522311626642393027129631

Offset

1,1

Comments

Conjecture: Sequence is infinite.

Links

Table of n, a(n) for n=1..13.

Maple

ds:=proc(s) local j: RETURN(add(s[j]*10^(j-1), j=1..nops(s))): end: a:=[]: k1:=1: for n from 1 to 50 do for k from k1 do m:=ds([1, seq(op(convert(a[i], base, 10)), i=1..nops(a)), op(convert(3*k, base, 10))]): if isprime(m) then k1:=k+1: a:=[op(a), 3*k]: break fi od od: seq(ds([1, seq(op(convert(a[i], base, 10)), i=1..j)]), j=1..nops(a)); # C. Ronaldo

Crossrefs

Cf. A089757.

Sequence in context: A028017 A028013 A028073 * A078891 A078914 A068147

Adjacent sequences: A089755 A089756 A089757 * A089759 A089760 A089761

Keyword

base,nonn

Author

Amarnath Murthy, Nov 22 2003

Extensions

More terms from C. Ronaldo (aga_new_ac(AT)hotmail.com), Dec 26 2004

Status

approved