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A108660 Square-loop primes. 4
2, 13, 31, 79, 97, 227, 881, 1013, 2797, 3181, 3631, 8101, 22727, 81001, 101363, 109013, 131363, 181813, 272227, 310181, 310901, 318181, 318881, 631013, 636313, 810401, 818101, 901097, 904097, 972227, 1018813, 1090013, 1810013, 2272727 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Primes such that each pair of adjacent digits (and also the first and the last ones) sums up to a square. First term is arguable since there is 'no pair of adjacent digits', but there are the "first" and "last" digits.

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..120

MATHEMATICA

Select[Prime[Range[200000]], And@@(IntegerQ[Sqrt[#]]&/@(Total/@Partition[ IntegerDigits[#], 2, 1, 1]))&] (* Harvey P. Dale, Mar 03 2014 *)

CROSSREFS

Cf. A046704, A007953, A088133, A088134, A088135, A088136, A108659.

Sequence in context: A158720 A108659 A086924 * A107132 A106959 A285096

Adjacent sequences:  A108657 A108658 A108659 * A108661 A108662 A108663

KEYWORD

nonn,base

AUTHOR

Zak Seidov, Jun 16 2005

STATUS

approved

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Last modified June 16 21:55 EDT 2021. Contains 345080 sequences. (Running on oeis4.)