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A200145 Primitive (squarefree) elements of A199745. 1
2145, 2730, 4641, 4845, 5005, 5610, 7410, 8778, 9177, 11305, 11730, 13485, 13585, 17017, 20010, 20930, 21489, 21505, 23529, 26445, 29946, 31465, 31857, 32538, 33649, 34410, 35409, 35581, 36685, 38570, 38874, 41106, 42441, 43401, 45066, 46189, 46345, 47730, 49569 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

MAPLE

Filter:= proc(n) local F;

  F:= ifactors(n)[2];

  if max(seq(f[2], f=F)) > 1 or nops(F) < 4 then return false fi;

  F:= map(t -> t[1], F);

  convert(F, `+`) = 2*(max(F)+min(F));

end proc:

select(Filter, [$1..10^5]); # Robert Israel, Dec 31 2015

MATHEMATICA

Select[Range[50000], Max@@Last/@(fi=FactorInteger[#])==1&&Plus@@(pl=First/@fi)/2==pl[[1]]+pl[[-1]]&] (*Ray Chandler, Nov 14 2011*)

CROSSREFS

Intersection of A199745 and A005117.

Sequence in context: A252547 A211601 A199745 * A179271 A118576 A259413

Adjacent sequences:  A200142 A200143 A200144 * A200146 A200147 A200148

KEYWORD

nonn

AUTHOR

Ray Chandler, Nov 14 2011

STATUS

approved

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Last modified November 18 11:51 EST 2019. Contains 329261 sequences. (Running on oeis4.)