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A154703
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Concatenation of the first n primes written in base 2.
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5
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10, 1011, 1011101, 1011101111, 10111011111011, 101110111110111101, 10111011111011110110001, 1011101111101111011000110011, 101110111110111101100011001110111, 10111011111011110110001100111011111101
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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EXAMPLE
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a(2) = 1011 = 10 Concat 11 = (2 base 2) Concat (3 base 2).
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MAPLE
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A154703 := proc(n) option remember: local d: if(n=1)then return 10: fi: d:=convert(ithprime(n), base, 2): return parse(cat(convert(procname(n-1), string), convert(op(convert(d, base, 10, 10^nops(d))), string))): end: seq(A154703(n), n=1..10); # Nathaniel Johnston, May 27 2011
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MATHEMATICA
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With[{p = IntegerDigits[Prime[Range[15]], 2]}, Array[FromDigits[Flatten[p[[;; #]]]] &, Length[p]]] (* Paolo Xausa, Feb 26 2024 *)
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PROG
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(PARI) a(n) = fromdigits(concat(apply(binary, primes(n)))); \\ Michel Marcus, Jul 17 2023
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CROSSREFS
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KEYWORD
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base,easy,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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