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 A199017 Number of partitions of n into distinct terms of (1,2)-Ulam sequence, cf. A002858. 7
 1, 1, 1, 2, 2, 2, 3, 3, 3, 4, 4, 5, 5, 6, 7, 7, 8, 9, 10, 11, 12, 13, 14, 14, 16, 16, 17, 19, 20, 22, 23, 25, 26, 27, 29, 30, 31, 34, 35, 38, 40, 41, 45, 45, 48, 51, 52, 57, 60, 62, 66, 68, 71, 75, 78, 83, 86, 93, 97, 100, 107, 109, 115, 120, 124, 132, 138 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 LINKS Eric Weisstein's World of Mathematics, Ulam Sequence Wikipedia, Ulam number EXAMPLE The first terms of A002858 are 1, 2, 3, 4, 6, 8, 11, 13, 16, 18, ... a(10) = #{8+2, 6+4, 6+3+1, 4+3+2+1} = 4; a(11) = #{11, 8+3, 8+2+1, 6+4+1, 6+3+2} = 5; a(12) = #{11+1, 8+4, 8+3+1, 6+4+2, 6+3+2+1} = 5. PROG (Haskell) a199017 = p a002858_list where    p _  0 = 1    p (u:us) m | m < u = 0               | otherwise = p us (m - u) + p us m CROSSREFS Cf. A000586; A199016, A199119, A199121, A199123. Sequence in context: A334415 A307152 A008671 * A189709 A025771 A154403 Adjacent sequences:  A199014 A199015 A199016 * A199018 A199019 A199020 KEYWORD nonn AUTHOR Reinhard Zumkeller, Nov 03 2011 STATUS approved

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Last modified December 2 08:31 EST 2021. Contains 349437 sequences. (Running on oeis4.)