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 A303362 Number of strict integer partitions of n with pairwise indivisible parts. 51
 1, 1, 1, 1, 2, 1, 3, 2, 3, 4, 5, 4, 6, 7, 7, 9, 11, 12, 13, 15, 17, 20, 23, 25, 27, 32, 35, 40, 45, 50, 55, 58, 67, 78, 84, 95, 101, 113, 124, 137, 153, 169, 180, 198, 219, 242, 268, 291, 319, 342, 374, 412, 450, 492, 535, 573, 632, 685, 746, 813, 868, 944 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,5 LINKS Fausto A. C. Cariboni, Table of n, a(n) for n = 1..450, (terms up to a(250) from Andrew Howroyd) EXAMPLE The a(14) = 7 strict integer partitions are (14), (11,3), (10,4), (9,5), (8,6), (7,5,2), (7,4,3). MATHEMATICA Table[Length[Select[IntegerPartitions[n], UnsameQ@@#&&Select[Tuples[#, 2], UnsameQ@@#&&Divisible@@#&]==={}&]], {n, 60}] PROG (PARI) lista(nn)={local(Cache=Map());   my(excl=vector(nn, n, sumdiv(n, d, 2^(n-d))));   my(a(n, m=n, b=0)=      if(n==0, 1,         while(m>n || bittest(b, 0), m--; b>>=1);         my(hk=[n, m, b], z);         if(!mapisdefined(Cache, hk, &z),           z = if(m, self()(n, m-1, b>>1) + self()(n-m, m, bitor(b, excl[m])), 0);           mapput(Cache, hk, z)); z));    for(n=1, nn, print1(a(n), ", ")) } \\ Andrew Howroyd, Nov 02 2019 CROSSREFS Cf. A000009, A000837, A003238, A006126, A051424, A259936, A275307, A281116, A285572, A285573, A290103, A293606, A293993, A303364. Sequence in context: A285779 A319320 A305194 * A183163 A338359 A122545 Adjacent sequences:  A303359 A303360 A303361 * A303363 A303364 A303365 KEYWORD nonn AUTHOR Gus Wiseman, Apr 22 2018 STATUS approved

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Last modified January 19 15:54 EST 2021. Contains 340270 sequences. (Running on oeis4.)