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A235376 Positions of 9's in A235354. 2
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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified June 16 14:16 EDT 2021. Contains 345057 sequences. (Running on oeis4.)