A062223 Numbers k such that the smoothly undulating palindromic number (74*10^k - 47)/99 is a prime.

5, 17, 2069, 6815, 20417, 25745

Offset

1,1

Comments

Prime versus probable prime status and proofs are given in the author's table.

No further terms < 100000. - Ray Chandler, Aug 17 2011

Links

Table of n, a(n) for n=1..6.

Patrick De Geest, SUPP Reference Table - 747

Index entries for sequences related to smoothly undulating palindromic primes

Example

k=17 -> (74*10^17 - 47)/99 = 74747474747474747.

Crossrefs

Cf. A062209-A062232, A059758, A032758.

Sequence in context: A172996 A253624 A085832 * A363759 A116911 A351890

Adjacent sequences: A062220 A062221 A062222 * A062224 A062225 A062226

Keyword

nonn,base,more

Author

Patrick De Geest and Hans Rosenthal (Hans.Rosenthal(AT)t-online.de), Jun 15 2001

Extensions

Edited by Ray Chandler, Aug 17 2011

Status

approved