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A171137
Smallest number m such that n-th prime = A171135(m).
2
1, 3, 21, 120, 884, 1199, 1736, 5801, 12757, 17651, 16136, 33461, 98009, 109754, 462331, 376523, 72206, 410384, 368531, 1399904, 1991081, 2063819, 1803503, 7056937, 3909176, 9747886, 10941734, 24616054
OFFSET
1,2
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..48
FORMULA
a(n) = MIN(m: A171135(m)=A000040(n));
A171135(a(n)) = A000040(n);
A171136(a(n)) = A000040(n) + 2*a(n).
PROG
(PARI) A171135(n)=forprime(p=2, , if(bigomega(p+2*n)<3, return(p)))
a(n)=my(p=prime(n), m); while(bigomega(p+2*m++)>2 || A171135(m)!=p, ); m \\ Charles R Greathouse IV, Oct 21 2014
(Haskell)
a171137 n = head [m | m <- [1..], a171135 m == a000040 n]
-- Reinhard Zumkeller, Oct 21 2014
CROSSREFS
Sequence in context: A068127 A247247 A322185 * A144884 A004658 A034552
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Dec 04 2009
EXTENSIONS
Definition corrected; thanks to Harvey P. Dale, who pointed out the mistake. - Reinhard Zumkeller, Oct 21 2014
a(20)-a(28) from Charles R Greathouse IV, Oct 21 2014
STATUS
approved