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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 (list; graph; refs; listen; history; text; internal format)
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?

LINKS

Table of n, a(n) for n=0..24.

FORMULA

A004185(A000108(n)) = A004185((2n)!/(n!(n+1)!)).

MATHEMATICA

FromDigits[Sort[IntegerDigits[#]]]&/@CatalanNumber[Range[0, 30]] (* Harvey P. Dale, Feb 26 2015 *)

CROSSREFS

Cf. A000108, A004185, A078726, A135374.

Sequence in context: A049939 A296302 A240401 * A057295 A290414 A288905

Adjacent sequences:  A133372 A133373 A133374 * A133376 A133377 A133378

KEYWORD

base,easy,nonn,less

AUTHOR

Jonathan Vos Post, Dec 21 2007

STATUS

approved

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Last modified August 8 05:50 EDT 2020. Contains 336290 sequences. (Running on oeis4.)