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A245808 Monoprimatic permutable numbers: Numbers whose decimal digits can be arranged to form exactly one prime number. No leading zeros. 5
2, 3, 5, 7, 11, 14, 16, 19, 23, 29, 32, 34, 35, 38, 41, 43, 47, 53, 59, 61, 67, 74, 76, 83, 89, 91, 92, 95, 98, 101, 103, 104, 106, 109, 110, 112, 115, 121, 130, 134, 140, 143, 145, 151, 154, 160, 166, 188, 190, 211, 223, 227, 229, 232, 233, 235, 236, 253, 257, 263, 269, 272, 275, 278, 287, 289, 292 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The sequence takes a surprisingly large number of computations to generate since the number of permutations rises quickly with the number of digits. Generating the sequence is an excellent programming exercise since there are several approaches to calculate the same sequence. Regardless of approach, there are many ways to optimize the algorithms, so the sequence would be a good choice of assignment for a contest between programmers. The assignment also has some pitfalls, mainly due to the problem of how to handle leading zeros.

The sequence was originally explored for the development of two puzzles found in the science fiction novel "The Right Left" by Andreas Boe.

REFERENCES

Andreas Boe, The Right Left, Amazon books, 2014.

LINKS

Andreas Boe, Table of n, a(n) for n = 1..9596

EXAMPLE

190 -> 019 (forbidden), 091 (forbidden), 109 (prime), 190 (even), 901 (composite), 910 (even) -> Conclusion: One prime number.

CROSSREFS

Cf. A246044 (Monoprimatic permutable primes), A246043 (Biprimatic permutable numbers), A246045 (Biprimatic permutable primes).

Sequence in context: A292238 A289863 A260904 * A252797 A325333 A036608

Adjacent sequences:  A245805 A245806 A245807 * A245809 A245810 A245811

KEYWORD

nonn,base

AUTHOR

Andreas Boe, Aug 22 2014

STATUS

approved

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Last modified August 5 07:33 EDT 2020. Contains 336209 sequences. (Running on oeis4.)