A335859 Terms of A334245 in increasing order and without repetition.
12, 15, 21, 30, 35, 57, 60, 65, 70, 77, 91, 105, 111, 114, 119, 126, 133, 143, 147, 150, 155, 165, 168, 180, 185, 190, 198, 209, 217, 220, 231, 234, 255, 260, 264, 294, 301, 310, 312, 319, 323, 330, 341, 360, 427, 432, 437, 455, 456, 462, 473, 497, 504, 510, 511, 546, 559, 588
Offset: 1
Keywords
Examples
l means: add least prime factor, and, L means: add largest prime factor. For 3: L: 3 + 3 = 6 l: 3 + 3 = 6 l: 6 + 2 = 8 L: 6 + 3 = 9 L: 8 + 2 = 10 l: 9 + 3 = 12 l: 10 + 2 = 12 So A334245(3) = 12 and 12 is a merging point with a(1) = 12. Now, for 12: L: 12 + 3 = 15 l: 12 + 2 = 14 l: 15 + 3 = 18 L: 14 + 7 = 21 L: 18 + 3 = 21 So A334245(12) = 21 and 21 is the merging point corresponding to 12 with a(3) = 21.
Links
- Robert Israel, Table of n, a(n) for n = 1..5939
- Bernard Schott and Blandine Schott, Network of merging points.
Crossrefs
Cf. A334245.
Programs
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Maple
N:= 1000: # to get all values <= N S:= x -> x + min(numtheory:-factorset(x)): T:= x -> x + max(numtheory:-factorset(x)): f:= proc(n) g(S(n),T(n),0,1) end proc: g:= proc(s,t,i,j) option remember; if max(s,t) > N then return 0 fi; if s = t and i=j then return s fi; if s <= t then if i = 0 then procname(T(s),t,1,j) else procname(S(s),t,0,j) fi elif j=0 then procname(s,T(t),i,1) else procname(s,S(t),i,0) fi end proc: sort(convert(map(f, {$2..N}) minus {0},list)); # Robert Israel, Jul 09 2020
Comments