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A028905
Arrange digits of primes in ascending order.
4
2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 13, 37, 14, 34, 47, 35, 59, 16, 67, 17, 37, 79, 38, 89, 79, 11, 13, 17, 19, 113, 127, 113, 137, 139, 149, 115, 157, 136, 167, 137, 179, 118, 119, 139, 179, 199, 112, 223, 227, 229, 233, 239, 124, 125, 257, 236, 269
OFFSET
1,1
COMMENTS
Leading zeros are discarded (e.g., 107, rearranged to 017, becomes 17).
LINKS
FORMULA
a(n) = A004185(A000040(n)). - Reinhard Zumkeller, Apr 03 2015
a(n) = prime(n) if prime(n) is in A028864. - Alonso del Arte, Nov 25 2019
EXAMPLE
The digits of 41 are 4, 1, which sorted are 1, 4; those are reinterpreted as 14.
The digits of 43 are 4, 3, which sorted are 3, 4; those are reinterpreted as 34.
The digits of 47 are 4, 7, which are already sorted, so 47 is not changed.
MATHEMATICA
Table[FromDigits[Sort[IntegerDigits[Prime[n]]]], {n, 100}] (* Alonso del Arte, Nov 25 2019 *)
PROG
(Haskell)
a028905 = a004185 . a000040 -- Reinhard Zumkeller, Apr 03 2015
(PARI) eva(n) = subst(Pol(n), x, 10)
a(n) = eva(vecsort(digits(prime(n)))) \\ Felix Fröhlich, Nov 25 2019
CROSSREFS
KEYWORD
nonn,base
EXTENSIONS
More terms from Patrick De Geest, April 1998
Offset corrected by Reinhard Zumkeller, Apr 03 2015
STATUS
approved