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%I #10 Jul 23 2023 22:27:28
%S 2,2,3,3,5,7,2,5,7,11,3,5,11,13,17,2,5,7,13,17,19,3,5,11,13,19,23,29,
%T 5,11,13,19,23,31,37,41,2,7,13,17,23,29,37,41,43,5,7,17,23,29,37,41,
%U 47,53,59,3,11,13,23,31,37,43,47,59,61,67,2,5,13,17,29
%N Triangular array: row n lists the primes indexed by the array in A363671.
%C Row n lists primes of the form prime(n+2)-2*k where A028334(n) <= k <= A067076(n).
%e First 10 rows:
%e 2
%e 2 4
%e 3 5 7
%e 2 5 7 11
%e 3 5 11 13 17
%e 2 5 7 13 17 19
%e 3 5 11 13 19 23 29
%e 5 11 13 19 23 31 37 41
%e 2 7 13 17 23 29 37 41 43
%e 5 7 17 23 29 37 41 47 53 59
%e For row 6, we have prime(8) = 19, and prime 19-2*k is prime for these k: 1, 3, 4, 6, 7, 8. The primes with indexes 1,3,4,6,7,8 are 2,5,7,13,17,19.
%t m[p_] := Select[Range[500], PrimeQ[p - 2 #] && p > 2 # &]
%t t = Prime[Table[m[Prime[n]], {n, 3, 15}]]
%t TableForm[t] (* this sequence as an array *)
%t Flatten[t] (* this sequence *)
%Y Cf. A000040, A087478 (column 1), A363671.
%K nonn,tabl
%O 1,1
%A _Clark Kimberling_, Jun 15 2023