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A160669
Smallest prime divisor of A160668(n).
2
2, 7, 5, 3, 89, 3, 83, 3, 7, 71, 3, 3, 59, 3, 53, 47, 41, 3, 3, 29, 3, 3, 17, 11, 3, 29, 3, 19, 3, 587, 3, 11, 863, 3, 23, 3, 3, 3, 7, 827, 821, 3, 809, 3, 11, 3, 3, 3, 773, 3, 13, 761, 3, 7, 743, 11, 17, 3, 3, 719, 3, 7, 3, 13, 3, 683, 3, 3, 653, 3, 647, 641, 3, 3, 3, 617, 13, 3, 599
OFFSET
1,1
EXAMPLE
a(1)=2 because in A160668 a(1)=8, so the first prime divisor is 2.
PROG
(UBASIC) 10 'recipseq, Enoch Haga, May 22 2009 20 N=3:print N:C=2 30 A=3:S=sqrt(N) 40 B=N/A 50 if A*B=int(N) then 70 60 A=A+2:if A<S then 40 70 if N=prmdiv(N) then print N; :else 130 80 if alen(N)=1 then print 10^1-N; :P=prmdiv(10^1-N):goto 120 90 if alen(N)=2 then print 10^2-N; :P=prmdiv(10^2-N):goto 120 100 if alen(N)=3 then print 10^3-N; :P=prmdiv(10^3-N):goto 120 110 if alen(N)=4 then print 10^4-N; :P=prmdiv(10^4-N) 120 print P; C:C=C+1:stop 130 N=N+2:S=sqrt(N):goto 40
CROSSREFS
Sequence in context: A171037 A246205 A340117 * A301816 A021367 A217102
KEYWORD
easy,nonn
AUTHOR
Enoch Haga, May 23 2009
STATUS
approved

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Last modified September 20 02:41 EDT 2024. Contains 376016 sequences. (Running on oeis4.)