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A030719
Number of new terms at stage n in the formation of A030717.
10
1, 1, 2, 2, 3, 3, 4, 5, 6, 7, 7, 8, 10, 12, 13, 16, 18, 20, 23, 25, 28, 31, 33, 36, 38, 41, 43, 45, 47, 50, 53, 56, 60, 62, 65, 69, 72, 78, 83, 86, 88, 92, 95, 99, 105, 110, 114, 117, 122, 125, 130, 136, 140, 144, 149, 153, 159, 162, 167, 173, 180, 184, 188
OFFSET
1,3
LINKS
Michael De Vlieger, Table of n, a(n) for n = 1..1024 (First 500 terms from Reinhard Zumkeller)
MATHEMATICA
nn = 63; c[_] = 0; r = k = a[1] = c[1] = 1; Reap[Do[w = Union@ Array[a, k]; Do[Set[a[j + k], c[w[[j]]]], {j, Length[w]}]; Do[c[a[j + k]]++, {j, Length[w]}]; k += Sow[Length[w]], {nn}]][[-1, -1]] (* Michael De Vlieger, Nov 15 2022 *)
PROG
(Haskell)
a030719 n = a030719_list !! (n-1)
a030719_list = tail $ zipWith (-) (tail a253170_list) a253170_list
-- Reinhard Zumkeller, Dec 28 2014
CROSSREFS
Sequence in context: A104408 A008718 A248958 * A126027 A111581 A116572
KEYWORD
nonn
STATUS
approved