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 A014643 Triangular array starting with {1,1}; then i-th term in a row gives number of i's in next row. 4
 1, 1, 1, 2, 1, 2, 2, 1, 2, 2, 3, 3, 1, 2, 2, 3, 3, 4, 4, 4, 5, 5, 5, 1, 2, 2, 3, 3, 4, 4, 4, 5, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8, 8, 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS The row {2} could be safely prepended to this triangle. - Gus Wiseman, May 13 2018 LINKS Alois P. Heinz, Rows n = 1..8, flattened EXAMPLE Triangle begins: {1,1}, {1,2}, {1,2,2}, {1,2,2,3,3}, ... MAPLE T:= proc(n) option remember; `if`(n=0, 2, (l->       seq(i\$l[i], i=1..nops(l)))([T(n-1)]))     end: seq(T(n), n=1..7);  # Alois P. Heinz, May 17 2018 MATHEMATICA NestList[Join@@Table[Table[i, {#[[i]]}], {i, Length[#]}]&, {2}, 8] (* Gus Wiseman, May 13 2018 *) CROSSREFS Rows converge to A001462. Cf. A011784, A012257, A014643, A014644, A112798, A181819, A182850-A182858, A296150, A304455. Sequence in context: A308694 A280521 A278043 * A236265 A238645 A118382 Adjacent sequences:  A014640 A014641 A014642 * A014644 A014645 A014646 KEYWORD tabf,nonn AUTHOR EXTENSIONS More terms from Patrick De Geest STATUS approved

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Last modified December 1 22:12 EST 2021. Contains 349435 sequences. (Running on oeis4.)