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A185511 Array: row n shows numbers m such that prime(m) is in row n of the natural number array A000027, by antidiagonals. 2

%I #4 Mar 30 2012 18:57:17

%S 1,4,2,5,3,6,10,7,11,8,12,9,34,17,13,19,15,44,29,20,18,22,28,80,37,23,

%T 25,14,33,40,95,55,60,67,21,16,43,51,143,85,76,110,31,30,46,47,71,221,

%U 109,194,127,45,41,145,26,59,91,243,155,252,181,61,52,244,38,24,75,103,314,175,349,202,63,72,316,42,32,27

%N Array: row n shows numbers m such that prime(m) is in row n of the natural number array A000027, by antidiagonals.

%C If the conjecture at A185510 is true, then the A185512, as a sequence, is a permutation of the natural numbers.

%e Start with the natural number array A000027:

%e 1...2...4...7

%e 3...5...8..12

%e 6...9..13..18

%e (The antidiagonals are 1; 2,3; 4,5,6; 7,8,9,10;...).

%e Primes, by rows (A185510):

%e 2.....7....11....29... in row 1 of A000027

%e 3.....5....17....23... in row 2

%e 13...31...139...193... in row 3, etc.

%e Now replace each prime by its index to obtain A185511.

%e Northwest corner:

%e 1.....4....5...10...12...19...22...33

%e 2.....3....7....9...15...28...40...51

%e 6....11...34...44...80...95..143..221

%e 8....17...29...37...55...85..109..155

%e 13...20...23...60...76..194..252..349

%t f[n_,k_]:=n+(k+n-2) (k+n-1)/2;

%t Do[t[n]={};Do[If[PrimeQ[f[n,k]],AppendTo[t[n],f[n,k]]],{k,1,1000}]; t[n];

%t u[n]={};Do[If[MemberQ[t[n],Prime[m]],AppendTo[u[n],m]],{m,1,1000}],{n,12}]

%t TableForm[Table[u[n],{n,12}]]

%Y Cf. A000027, A000040, A185510.

%K nonn,tabl

%O 1,2

%A _Clark Kimberling_, Jan 29 2011

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Last modified April 16 03:28 EDT 2024. Contains 371696 sequences. (Running on oeis4.)