S000916


Left- or right-truncatable primes in base 3.

2, 5, 7, 17, 23, 53, 71, 233, 701, 719

1

S000916

These numbers must be converted to base 3 and then truncated. For instance, the number 71 is 2122(3).

T. D. Noe, Plot of 10 terms

See references in  A137812.

(Mma) b = 3; Clear[s]; n = 0; s[n] = Prime[Range[PrimePi[b-1]]]; While[cnt = 0; lst = Reap[Do[k = s[n][[i]]; Do[p = j*b^(n+1) + k; If[PrimeQ[p], Sow[p]; cnt++], {j, b-1}]; Do[p = b*k + j; If[PrimeQ[p], Sow[p]; cnt++], {j, b-1}], {i, Length[s[n]]}]]; cnt > 0, n++; s[n] = Union[lst[[2,1]]]]; t = s[0]; Do[t = Join[t, s[i]], {i, n}]; t

Cf. A137812 (base 10), S000910-S000915 (bases 9 to 4), S000917.

nonn,base,full

T. D. Noe, Jun 21 2016

© Tony D Noe 2014-2016