A235376 Positions of 9's in A235354.

58, 167, 244, 300, 310, 326, 348, 361, 380, 394, 422, 493, 520, 525, 560, 574, 677, 826, 877, 935, 938, 1010, 1049, 1116, 1168, 1201, 1210, 1212, 1334, 1346, 1382, 1411, 1433, 1585, 1591, 1640, 1683, 1750, 1790, 1796, 1805, 1848, 1858, 1891, 1997, 2032, 2114

Offset

1,1

Comments

If prime(a(n)) is written in base k, 2<=k<=9, and the k-representation is read in decimal, then it will be a prime only for k=9.

Links

Table of n, a(n) for n=1..47.

Prog

(PARI) isok(n) = {my(p = prime(n)); for (b = 2, 8, if (isprime(subst(Pol(digits(p, b)), x, 10)), return(0)); ); isprime(subst(Pol(digits(p, 9)), x, 10)); } \\ Michel Marcus, Jan 18 2014

Crossrefs

Cf. A000040, A235354.

Sequence in context: A044390 A044771 A127025 * A067914 A250800 A172357

Adjacent sequences: A235373 A235374 A235375 * A235377 A235378 A235379

Keyword

nonn,base

Author

Vladimir Shevelev and Peter J. C. Moses, Jan 08 2014

Status

approved