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A104224
Sum of the smallest and the largest n-digit primes.
1
9, 108, 1098, 10982, 109998, 1099986, 10999994, 110000008, 1099999944, 10999999974, 109999999996, 1099999999992, 11000000000010, 110000000000010, 1100000000000020, 10999999999999974, 110000000000000058
OFFSET
1,1
EXAMPLE
The first term is 9 since it is the sum of 2 and 7, the smallest and largest of 1-digit primes.
PROG
(Sage) def A104224(n): return next_prime(10**(n-1))+previous_prime(10**n) # [D. S. McNeil, Feb 03 2011]
CROSSREFS
Sequence in context: A374071 A249048 A080505 * A099676 A268839 A214668
KEYWORD
nonn,base
AUTHOR
Parthasarathy Nambi, Apr 01 2005
STATUS
approved