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A225890 Composite numbers n such that A179382((n+1)/2)=(n-1)/(2^c) for some c > 0. 1
92673, 143713, 3579553, 4110529, 28688897, 127017857, 141127681, 157648097, 162101441 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
a(10) > 180*10^6. All terms up to a(9) are of the form 32*k+1 and except a(1) are also semiprimes. The numbers 212999489, 393300097 and 663414881 are also terms. - Giovanni Resta, May 21 2013
LINKS
EXAMPLE
143713=137*1049: A179382((143713+1)/2)=4491=(143713-1)/(2^5)
PROG
(PARI) oddres(n)=n>>valuation(n, 2)
cyc(d)=my(k=1, t=1); while((t=oddres(t+d))>1, k++); k
p=5; forprime(q=7, 1e7, forstep(n=p+2, q-2, 2, my(t=(n-1)/cyc(n), c=valuation(t, 2)); if(t>>c==1 && c>0, print1(n", "))); p=q) \\ Charles R Greathouse IV, May 20 2013
CROSSREFS
Cf. A179382.
Sequence in context: A182657 A251069 A184560 * A183853 A331361 A128277
KEYWORD
nonn,more
AUTHOR
Lear Young and Peter Košinár, May 20 2013
EXTENSIONS
Missing a(3) from Giovanni Resta, May 20 2013
a(6)-a(9) from Giovanni Resta, May 21 2013
STATUS
approved

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Last modified July 18 01:34 EDT 2024. Contains 374377 sequences. (Running on oeis4.)