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A133375
Catalan numbers with digits sorted in increasing order and zeros suppressed.
0
1, 1, 2, 5, 14, 24, 123, 249, 134, 2468, 16679, 56788, 1228, 2479, 244467, 4456899, 3355677, 12446799, 3467778, 112366779, 12244566, 222446667, 1234456689, 1333455669, 112234447899
OFFSET
0,3
COMMENTS
This is to A000108 as A135374 is to A000225 and as A078726 is to A000215. Of the values through a(24), the only primes are the two prime Catalan numbers 2 and 5. What is the first prime in this sequence which is not an untransformed Catalan number?
FORMULA
A004185(A000108(n)) = A004185((2n)!/(n!(n+1)!)).
MATHEMATICA
FromDigits[Sort[IntegerDigits[#]]]&/@CatalanNumber[Range[0, 30]] (* Harvey P. Dale, Feb 26 2015 *)
CROSSREFS
KEYWORD
base,easy,nonn,less
AUTHOR
Jonathan Vos Post, Dec 21 2007
STATUS
approved