S000914


Left- or right-truncatable primes in base 5.

2, 3, 7, 11, 13, 17, 19, 23, 37, 59, 61, 67, 73, 89, 97, 107, 113, 307, 311, 317, 337, 347, 367, 449, 487, 569, 607, 613, 1559, 1567, 1597, 1699, 2437, 2837, 3037, 3067, 7817, 7949, 15187, 39089, 39199, 39749, 75937, 77687, 195997, 232187, 352249, 979987, 4886237

1

S000914

These numbers must be converted to base 5 and then truncated. For instance, the number 101 is 412(5).

T. D. Noe, Plot of 49 terms

See references in  A137812.

(Mma) b = 5; 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-S000916 (bases 9 to 3), S000917.

nonn,base,full

T. D. Noe, Jun 21 2016

© Tony D Noe 2014-2016