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A344891 Divide the primes into subsets of lengths given by successive primes, then reverse the order of terms in each subset.

%I A344891 #17 Sep 05 2023 12:22:04
%S A344891 3,2,11,7,5,29,23,19,17,13,59,53,47,43,41,37,31,107,103,101,97,89,83,
%T A344891 79,73,71,67,61,179,173,167,163,157,151,149,139,137,131,127,113,109,
%U A344891 271,269,263,257,251,241,239,233,229,227,223,211,199,197,193,191,181
%N A344891 Divide the primes into subsets of lengths given by successive primes, then reverse the order of terms in each subset.
%C A344891 Irregular triangle read by rows in which row n lists the next p primes in decreasing order, where p is the n-th prime, with n >= 1.
%H A344891 Harvey P. Dale, <a href="/A344891/b344891.txt">Table of n, a(n) for n = 1..1000</a>
%e A344891 Written as an irregular triangle in which row lengths give A000040 the sequence begins:
%e A344891     3,   2;
%e A344891    11,   7,   5;
%e A344891    29,  23,  19,  17,  13;
%e A344891    59,  53,  47,  43,  41,  37,  31;
%e A344891   107, 103, 101,  97,  89,  83,  79,  73,  71,  67,  61;
%e A344891   179, 173, 167, 163, 157, 151, 149, 139, 137, 131, 127, 113, 109;
%e A344891   ...
%t A344891 Module[{nn=10,p},p=Total[Prime[Range[nn]]];Flatten[Reverse/@TakeList[ Prime[ Range[ p]],Prime[Range[nn]]]]] (* _Harvey P. Dale_, Sep 14 2022 *)
%Y A344891 Right border gives A180302.
%Y A344891 Row lengths give A000040.
%Y A344891 Row products give A119645.
%Y A344891 Row sums give A034958.
%Y A344891 Cf. A343809.
%K A344891 nonn,tabf
%O A344891 1,1
%A A344891 _Paolo Xausa_, Jun 01 2021