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 A002871 a(n) = max_{k=0..n} 2^k*A048993(n,k) (Formerly M1261 N0483) 2
 1, 2, 4, 12, 48, 200, 1040, 5600, 33600, 222432, 1460928, 11487168, 84713728, 731574272, 6314147840, 55456727040, 548291597568, 5226494727168, 54361802626560, 586042688924160, 6149776714099200, 72895623466265600, 855187250563024896 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Original name: Sorting numbers (see Motzkin article for details). For n>0, a(n) is also the maximum term in row n of the triangle in A227450. - Danny Rorabaugh, Oct 24 2015 REFERENCES N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence). N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). LINKS Alois P. Heinz, Table of n, a(n) for n = 0..250 T. S. Motzkin, Sorting numbers for cylinders and other classification numbers, in Combinatorics, Proc. Symp. Pure Math. 19, AMS, 1971, pp. 167-176. [Annotated, scanned copy] OEIS Wiki, Sorting numbers FORMULA a(n) = max{2^k*stirling2(n,k), k=0..n}. - Sean A. Irvine, Mar 26 2013 MAPLE a:= n-> max(seq(2^k*Stirling2(n, k), k=0..n)): seq(a(n), n=0..30);  # Alois P. Heinz, Mar 26 2013 MATHEMATICA a[n_] := Max[Table[2^k*StirlingS2[n, k], {k, 0, n}]]; Table[a[n], {n, 0, 30}] (* Jean-François Alcover, Feb 25 2015 *) PROG (PARI) a(n) = vecmax(vector(n+1, k, 2^(k-1)*stirling(n, k-1, 2))); \\ Michel Marcus, Feb 25 2015 CROSSREFS Cf. A008277, A048993, A227450. Sequence in context: A277281 A172452 A004527 * A013172 A321009 A052849 Adjacent sequences:  A002868 A002869 A002870 * A002872 A002873 A002874 KEYWORD nonn,nice AUTHOR EXTENSIONS More terms from Sean A. Irvine, Mar 26 2013 New name from Danny Rorabaugh, Oct 24 2015 STATUS approved

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Last modified December 13 23:14 EST 2019. Contains 329974 sequences. (Running on oeis4.)