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Square array, read by descending antidiagonals: row n lists the primes whose base-2 representation has exactly n ones, starting from n=3.
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%I #34 Jan 19 2024 08:13:57

%S 7,11,23,13,29,31,19,43,47,311

%N Square array, read by descending antidiagonals: row n lists the primes whose base-2 representation has exactly n ones, starting from n=3.

%e Corner:

%e n=3: 7 11 13 19 37 41 67 73 97

%e n=4: 23 29 43 53 71 83 89 101 113

%e n=5: 31 47 59 61 79 103 107 109 151

%e n=6: 311 317 347 349 359 373 461 467 571

%e The first four primes in row n=3 have these base-2 representations, respectively: 111, 1011, 1101, 10011.

%t t[n_] := Count[IntegerDigits[Prime[n], 2], 1] (* A014499 *)

%t u = Table[t[n], {n, 1, 200}];

%t p[n_] := Flatten[Position[u, n]]

%t w = TableForm[Table[Prime[p[n]], {n, 3, 16}]]

%Y Cf. A000040, A014499.

%Y Cf. A019434 (row 2), A061712 (column 1), A081091 (row 3), A095077 (row 4).

%K nonn,base,tabl,more

%O 3,1

%A _Clark Kimberling_, May 11 2023

%E New offset and edited by _Michel Marcus_, Jan 19 2024