A119351 Indices k of prime palindromic numbers formed by taking k digits in the decimal expansion of Pi and reflecting about the last digit.

1, 2, 27, 151, 461, 2056

Offset

1,2

Comments

The primes corresponding to these indices are A039954.

a(7) > 50000. - Michael S. Branicky, Feb 11 2025

Links

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

Example

Of 3, 313, 31413, 3141413, 314151413, the first and second are primes, so the first two terms are 1 and 2.

Crossrefs

Cf. A039954.

Sequence in context: A280089 A041801 A166942 * A098627 A263930 A051766

Adjacent sequences: A119348 A119349 A119350 * A119352 A119353 A119354

Keyword

nonn,more,base,changed

Author

Eric W. Weisstein, May 15 2006; corrected May 27 2006

Status

approved