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A276201
Largest prime < A019518(n).
0
19, 233, 2351, 235699, 23571103, 2357111297, 235711131709, 23571113171891, 2357111317192243, 235711131719232929, 23571113171923293127, 2357111317192329313727, 235711131719232931374061, 23571113171923293137414303, 2357111317192329313741434739, 235711131719232931374143475271
OFFSET
2,1
COMMENTS
The complement of A074366.
LINKS
Eric Weisstein's World of Mathematics, Previous Prime
FORMULA
a(n) = A151799(A019518(n)).
a(n) = A000040(A000720(A019518(n)-1)).
EXAMPLE
a(5) = 235699, because this is the largest prime less than 235711 (concatenation of first 5 primes, written in decimal system).
MATHEMATICA
Table[NextPrime[FromDigits[Flatten[IntegerDigits[Prime[Range[n]]]]], -1], {n, 2, 17}]
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Ilya Gutkovskiy, Aug 24 2016
STATUS
approved