login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..79.

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

Cf. A160668 A160670

Sequence in context: A138344 A171037 A246205 * A301816 A021367 A217102

Adjacent sequences:  A160666 A160667 A160668 * A160670 A160671 A160672

KEYWORD

easy,nonn

AUTHOR

Enoch Haga, May 23 2009

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 13 16:32 EDT 2019. Contains 327966 sequences. (Running on oeis4.)