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A362979
Square array, read by descending antidiagonals: row n lists the primes whose base-2 representation has exactly n ones, starting from n=3.
0
7, 11, 23, 13, 29, 31, 19, 43, 47, 311
OFFSET
3,1
EXAMPLE
Corner:
n=3: 7 11 13 19 37 41 67 73 97
n=4: 23 29 43 53 71 83 89 101 113
n=5: 31 47 59 61 79 103 107 109 151
n=6: 311 317 347 349 359 373 461 467 571
The first four primes in row n=3 have these base-2 representations, respectively: 111, 1011, 1101, 10011.
MATHEMATICA
t[n_] := Count[IntegerDigits[Prime[n], 2], 1] (* A014499 *)
u = Table[t[n], {n, 1, 200}];
p[n_] := Flatten[Position[u, n]]
w = TableForm[Table[Prime[p[n]], {n, 3, 16}]]
CROSSREFS
Cf. A019434 (row 2), A061712 (column 1), A081091 (row 3), A095077 (row 4).
Sequence in context: A345680 A175651 A372045 * A284052 A211433 A039511
KEYWORD
nonn,base,tabl,more
AUTHOR
Clark Kimberling, May 11 2023
EXTENSIONS
New offset and edited by Michel Marcus, Jan 19 2024
STATUS
approved