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A359978
Prime numbers whose decimal representation can be split into two nonempty parts without leading 0, say x and y (in that order), and such that the concatenation of y and x yields a different prime number.
1
13, 17, 31, 37, 71, 73, 79, 97, 113, 127, 131, 149, 157, 163, 173, 181, 191, 197, 199, 271, 277, 311, 313, 317, 331, 337, 359, 367, 373, 379, 397, 419, 479, 491, 571, 577, 593, 617, 631, 673, 719, 727, 733, 739, 757, 761, 787, 797, 811, 839, 877, 911, 919, 937
OFFSET
1,1
EXAMPLE
The first terms, alongside the corresponding other prime numbers, are:
n a(n) Other prime numbers
-- ---- -------------------
1 13 {31}
2 17 {71}
3 31 {13}
4 37 {73}
5 71 {17}
6 73 {37}
7 79 {97}
8 97 {79}
9 113 {131, 311}
10 127 {271}
11 131 {113, 311}
12 149 {491}
PROG
(PARI) See Links section.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Rémy Sigrist, Jan 20 2023
STATUS
approved