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A174185 Numbers k such that the k-th prime minus the k-th even nonprime is prime. 0
1, 7, 8, 9, 12, 15, 19, 20, 21, 23, 24, 25, 30, 32, 33, 34, 35, 36, 37, 39, 41, 42, 45, 46, 48, 51, 56, 63, 67, 71, 75, 78, 81, 82, 85, 86, 88, 89, 90, 96, 102, 107, 112, 115, 116, 117, 120, 121, 123, 126, 128, 132, 135, 137, 146, 150, 152, 153, 156, 158, 159, 163, 164 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Numbers k such that prime(k) - (even nonprime)(k) is prime.
LINKS
EXAMPLE
1 is a term because A000040(1) - A163300(1) = 2 (prime);
7 is a term because A000040(7) - A163300(7) = 3 (prime).
MAPLE
A163300 := proc(n) option remember ; if n = 1 then 0; else for a from procname(n-1)+2 by 2 do if not isprime(a) then return a ; end if; end do; end if; end proc:
for n from 1 to 300 do if isprime( ithprime(n) - A163300(n)) then printf("%d, ", n) ; end if; end do: # R. J. Mathar, Apr 20 2010
CROSSREFS
Sequence in context: A192050 A045158 A074328 * A309152 A170933 A297257
KEYWORD
nonn
AUTHOR
EXTENSIONS
Corrected (11 replaced with 12) by R. J. Mathar, Apr 20 2010
STATUS
approved

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Last modified June 18 17:48 EDT 2024. Contains 373483 sequences. (Running on oeis4.)