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A257851 Triangle read by rows: row n contains the first n+1 numbers m such that A046660(m) = n.

%I A257851 #47 Sep 17 2021 16:50:22
%S A257851 1,4,9,8,24,27,16,48,72,80,32,96,144,160,216,64,192,288,320,432,448,
%T A257851 128,384,576,640,864,896,1296,256,768,1152,1280,1728,1792,2592,2816,
%U A257851 512,1536,2304,2560,3456,3584,5184,5632,6400,1024,3072,4608,5120,6912,7168,10368,11264,12800,13312
%N A257851 Triangle read by rows: row n contains the first n+1 numbers m such that A046660(m) = n.
%C A257851 At the suggestion of _Michel Marcus_'s remark in _Carlos Eduardo Olivieri_'s A261256.
%H A257851 Reinhard Zumkeller, <a href="/A257851/b257851.txt">Rows n = 0..20 of triangle, flattened</a>
%F A257851 T(n,0) = A151821(n+1);
%F A257851 T(n,n-1) = A261256(n) for n > 0;
%F A257851 T(n,n) = A264959(n).
%F A257851 T(0,0) = A005117(1);
%F A257851 T(1,k) = A060687(k+1), k = 0..1;
%F A257851 T(2,k) = A195086(k+1), k = 0..2;
%F A257851 T(3,k) = A195087(k+1), k = 0..3;
%F A257851 T(4,k) = A195088(k+1), k = 0..4;
%F A257851 T(5,k) = A195089(k+1), k = 0..5;
%F A257851 T(6,k) = A195090(k+1), k = 0..6;
%F A257851 T(7,k) = A195091(k+1), k = 0..7;
%F A257851 T(8,k) = A195092(k+1), k = 0..8;
%F A257851 T(9,k) = A195093(k+1), k = 0..9;
%F A257851 T(10,k) = A195069(k+1), k = 0..10.
%e A257851 0:    1
%e A257851 1:    4     9
%e A257851 2:    8    24      27
%e A257851 3:   16    48      72    80
%e A257851 4:   32    96     144   160     216
%e A257851 5:   64   192     288   320     432   448
%e A257851 6:  128   384     576   640     864   896    1296
%e A257851 7:  256   768    1152  1280    1728  1792    2592   2816
%e A257851 8:  512  1536    2304  2560    3456  3584    5184   5632    6400
%e A257851 --  ------------------------------------------------------------
%e A257851 0:  1
%e A257851 1:  2^2   3^2
%e A257851 2:  2^3 2^3*3     3^3
%e A257851 3:  2^4 2^4*3 2^3*3^2 2^4*5
%e A257851 4:  2^5 2^5*3 2^4*3^2 2^5*5 2^3*3^3
%e A257851 5:  2^6 2^6*3 2^5*3^2 2^6*5 2^4*3^3 2^6*7
%e A257851 6:  2^7 2^7*3 2^6*3^2 2^7*5 2^5*3^3 2^7*7 2^4*3^4
%e A257851 7:  2^8 2^8*3 2^7*3^2 2^8*5 2^6*3^3 2^8*7 2^5*3^4 2^8*11
%e A257851 8:  2^9 2^9*3 2^8*3^2 2^9*5 2^7*3^3 2^9*7 2^6*3^4 2^9*11 2^8*5^2
%t A257851 T[n_] := Reap[For[m = 1; k = 1, k <= n+1, If[PrimeOmega[m] - PrimeNu[m] == n, Sow[m]; k++]; m++]][[2, 1]];
%t A257851 Table[T[n], {n, 0, 10}] // Flatten (* _Jean-François Alcover_, Sep 17 2021 *)
%o A257851 (Haskell)
%o A257851 a257851 n k = a257851_tabl !! n !! k
%o A257851 a257851_row n = a257851_tabl !! n
%o A257851 a257851_tabl = map
%o A257851    (\x -> take (x + 1) $ filter ((== x) . a046660) [1..]) [0..]
%Y A257851 Cf. A046660, A151821, A261256.
%Y A257851 Cf. A005117, A060687, A195086, A195087, A195088, A195089, A195090, A195091, A195092, A195093, A195069.
%K A257851 nonn,tabl
%O A257851 0,2
%A A257851 _Reinhard Zumkeller_, Nov 29 2015