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 A236240 Multiples of 6 that either are Averages of Twin Prime Pairs (ATPP), or become ATPP when multiplied by 3. 1
 6, 12, 18, 24, 30, 36, 42, 60, 66, 72, 90, 102, 108, 138, 144, 150, 174, 180, 192, 198, 228, 240, 270, 276, 282, 294, 312, 348, 354, 384, 420, 426, 432, 462, 522, 540, 570, 600, 618, 624, 642, 660, 666, 696, 714, 756, 780, 810, 822, 828, 858, 864, 882, 930 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The first 10k terms of this sequence are 45.37% pseudo ATPP, and are about 9.71% of all multiples of 6 up to 617694.  All numbers in this sequence that end 4 or 6 are ATPP/3 (but the reverse is not true). LINKS Michael G. Kaarhus, Table of n, a(n) for n = 1..10000 EXAMPLE 660 is in this sequence because it is an ATPP.  666 is in this sequence because 666 * 3 = 1998 is an ATPP. PROG (Maxima) load(basic)\$ a:[]\$ p:-1\$ j:0\$ m:0\$ chli():= block (if w>341550071728321 then    (n:11000, print("# over limit") ), return)\$ for n:1 thru 10000 step 0 do    (p:p+6, q:p+1, r:p+2, if (primep(p) and primep(r)) then       (push(q, a), n:n+1, j:j+1) else          (w:3*q, chli(), if (primep(w-1) and primep(w+1)) then             (push(q, a), n:n+1, m:m+1    )     )  )\$ a:reverse(a)\$ d:length(a)\$ k:float(m*100/d)\$ h:", "\$ y:last(a)\$ b:float(d*100/(y/6))\$ print("# Real ATPP = ", j, h, " Pseudo ATPP = ", m, h, " Percent pseudo = ", k)\$ print("# First ", d, " of sequence are ", b, "% of ints. up to ", y, " cong. to 0 mod 6.")\$ for i:1 thru d do (s:pop(a), print(i, h, s) )\$ CROSSREFS Subsequence of A008588 (Multiples of 6) Sequence in context: A078596 A187389 A085129 * A242650 A083263 A194385 Adjacent sequences:  A236237 A236238 A236239 * A236241 A236242 A236243 KEYWORD nonn AUTHOR Michael G. Kaarhus, Jan 20 2014 STATUS approved

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Last modified May 18 22:08 EDT 2022. Contains 353825 sequences. (Running on oeis4.)