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 A239656 First differences of sphenic numbers, cf. A007304. 5
 12, 24, 4, 8, 24, 3, 5, 4, 16, 8, 16, 11, 5, 4, 8, 4, 4, 5, 27, 8, 1, 7, 8, 9, 3, 8, 7, 9, 3, 1, 4, 20, 8, 4, 23, 9, 3, 9, 4, 4, 11, 14, 3, 4, 4, 8, 8, 3, 1, 4, 1, 3, 4, 13, 10, 5, 4, 9, 11, 4, 8, 12, 12, 4, 21, 6, 13, 8, 8, 5, 3, 4, 4, 3, 1, 5, 3, 9, 11, 4 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(n) = A007304(n+1) - A007304(n); see A239673 and A239674 for record values and where they occur: A239673(n) = a(A239674(n)). LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..10000 MAPLE A007304 := proc(n)     option remember;     if n = 1 then         30;     else         for a from procname(n-1)+1 do             if numtheory[bigomega](a) =3 and nops(numtheory[factorset](a)) = 3 then                 return a;             end if;         end do:     end if; end proc: A239656 := proc(n)     A007304(n+1)-A007304(n) ; end proc: MATHEMATICA With[{upto=1000}, Differences[Sort[Select[Times@@@Subsets[Prime[ Range[ Ceiling[upto/6]]], {3}], #<=upto&]]]] (* Harvey P. Dale, Jan 08 2015 *) PROG (Haskell) a239656 n = a239656_list !! (n-1) a239656_list = zipWith (-) (tail a007304_list) a007304_list CROSSREFS Cf. A065516. Sequence in context: A333933 A015447 A072822 * A059161 A133491 A075606 Adjacent sequences:  A239653 A239654 A239655 * A239657 A239658 A239659 KEYWORD nonn AUTHOR Reinhard Zumkeller, Mar 23 2014 STATUS approved

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Last modified April 10 08:09 EDT 2021. Contains 342845 sequences. (Running on oeis4.)