1,3
Primality up to Catalan[4250]+1 proved by PrimeForm.
Catalan[25]+1=50!/25!/26!+1=4861946401453 is prime.
Cf. A000108, A053427.
Sequence in context: A047775 A001432 A127075 this_sequence A104237 A085945 A005469
Adjacent sequences: A053426 A053427 A053428 this_sequence A053430 A053431 A053432
nonn
David Broadhurst (D.Broadhurst(AT)open.ac.uk), Jan 10 2000
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