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 A271641 Quantity of ancestors for n (in the sense explained below) 0
 9, 17, 15, 13, 11, 9, 7, 5, 3, 1, 17, 32, 29, 25, 21, 17, 13, 9, 5, 2, 15, 28, 26, 23, 19, 15, 11, 7, 4, 2, 13, 24, 22, 20, 17, 13, 9, 6, 4, 2, 11, 20, 18, 16, 14, 11, 8, 6, 4, 2, 9, 16, 14, 12, 10, 9, 8, 6, 4, 2, 7, 12, 10, 8, 7, 7, 7, 6, 4, 2, 5, 8, 6, 5, 5, 5, 5, 5, 4, 2, 3, 4, 3, 3, 3, 3, 3, 3, 3, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 17, 32 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS See A271639 for the definition of an ancestor. LINKS Table of n, a(n) for n=0..101. EXAMPLE "0" has 9 ancestors, which are 11, 22, 33, 44, 55, 66, 77, 88 and 99; "1" has 17 ancestors, which are 10, 12, 21, 23, 32, 34, 43, 45, 54, 56, 65, 67, 76, 78, 87, 89, 98; "2" has 15 ancestors, which are 13, 20, 24, 31, 35, 42, 46, 53, 57, 64, 68, 75, 79, 86, 97; "3" has 13 ancestors, etc. Thus the sequence starts with 9, 17, 15, 13, etc. CROSSREFS Cf. A271639. Sequence in context: A190322 A184938 A103707 * A292410 A004751 A134104 Adjacent sequences: A271638 A271639 A271640 * A271642 A271643 A271644 KEYWORD nonn,base AUTHOR Eric Angelini and Jean-Marc Falcoz, Apr 11 2016 STATUS approved

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Last modified March 1 19:16 EST 2024. Contains 370443 sequences. (Running on oeis4.)