A276132 - OEIS

A276132

Terms of A077390 with reverse in A077390.

2, 3, 5, 7, 11, 13, 17, 31, 37, 71, 73, 79, 97, 131, 151, 157, 179, 337, 353, 359, 373, 727, 733, 739, 751, 757, 929, 937, 953, 971, 1733, 1979, 3319, 3371, 3373, 3719, 3733, 7177, 7717, 9133, 9173, 9791

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OFFSET

1,1

COMMENTS

A subsequence of the reversible primes (A007500).

Inspired by Aug. 2016 SeqFan discussion about arrays of primes.

Questions: 1) What is the largest N X N square of decimal digits whose rows, columns and main diagonals are (non-palindromic) terms of this sequence?

The digits of each remaining smaller square formed by removing the outermost layer of digits of a given such square also form terms of this sequence. 2) What is the maximum number of distinct terms of this sequence that can appear in the rows, columns and diagonals of a single N X N square and of all its nested (N-2) X (N-2), (N-4) X (N-4), ..., 2 X 2 or 1 X 1 squares?

3) What is the maximum number of such consecutively nested squares comprised in total of only distinct primes?

LINKS

Table of n, a(n) for n=1..42.

EXAMPLE

9791 is a term because 9791, 79, 1979 and 97 are all prime numbers.

CROSSREFS

Cf. A077390, A007500.

Sequence in context: A090934 A068652 A003459 * A202264 A377266 A253717

Adjacent sequences: A276129 A276130 A276131 * A276133 A276134 A276135

KEYWORD

nonn,base,fini

AUTHOR

Rick L. Shepherd, Aug 21 2016

STATUS

approved