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 A277343 a(1) is 4. a(n) is the least semiprime q (A001358) greater than p = a(n-1), such that p/q is a new minimum. 1
 4, 6, 10, 21, 46, 106, 247, 579, 1363, 3214, 7586, 17915, 42311, 99931, 236023, 557455, 1316638, 3109733, 7344803, 17347513, 40972678, 96772393, 228564417, 539840885, 1275037411, 3011480697, 7112745019, 16799424206, 39678162637, 93714913738, 221343037931, 522784885426, 1234753254431 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Inspired by and analogous to A265418. p/q -> 0.423392190744304142156851442297311481582158896664... LINKS Robert G. Wilson v, Table of n, a(n) for n = 1..200 EXAMPLE 4/6 is 0.666... is a new low or minimum; 6/9 is 0.666... is not a new minimum, but; 6/10 is 0.600... is a new minimum; 10/21 is 0.476... is a new minimum; 21/46 is 0.456... is a new minimum; ... 522784885426/1234753254431 is 0.423... is a new minimum; etc. MAPLE with(numtheory): P:=proc(q) local a, b, n; a:=4; c:=a; print(a); for n from a+1 to q do if issqrfree(n) and nops(ifactors(n)[2])=2 then if a/n

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Last modified January 27 17:58 EST 2020. Contains 331296 sequences. (Running on oeis4.)