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 A305936 Irregular triangle whose n-th row is the multiset spanning an initial interval of positive integers with multiplicities equal to the n-th row of A296150 (the prime indices of n in weakly decreasing order). 44
 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 3, 1, 1, 2, 2, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 2, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 2, 1, 2, 3, 4, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 3, 1, 1, 1, 1, 2, 2, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,5 LINKS EXAMPLE Row 90 is {1,1,1,2,2,3,3,4} because 90 = prime(3)*prime(2)*prime(2)*prime(1). Triangle begins:    1:    2:  1    3:  1  1    4:  1  2    5:  1  1  1    6:  1  1  2    7:  1  1  1  1    8:  1  2  3    9:  1  1  2  2   10:  1  1  1  2   11:  1  1  1  1  1   12:  1  1  2  3   13:  1  1  1  1  1  1 MATHEMATICA nrmptn[n_]:=Join@@MapIndexed[Table[#2[[1]], {#1}]&, If[n==1, {}, Flatten[Cases[FactorInteger[n]//Reverse, {p_, k_}:>Table[PrimePi[p], {k}]]]]]; Array[nrmptn, 30] CROSSREFS Row lengths are A056239. Number of distinct elements in row n is A001222(n). Number of distinct multiplicities in row n is A001221(n). Cf. A000041, A000720, A112798, A181821, A182850, A255906, A296150, A304464. Cf. A318283, A318284, A318285, A318286, A318287, A318360, A318361, A318362, A318371. Sequence in context: A108775 A300826 A334926 * A339790 A334924 A211111 Adjacent sequences:  A305933 A305934 A305935 * A305937 A305938 A305939 KEYWORD nonn,tabf AUTHOR Gus Wiseman, Aug 23 2018 STATUS approved

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Last modified July 27 15:29 EDT 2021. Contains 346307 sequences. (Running on oeis4.)