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A154703
Concatenation of the first n primes written in base 2.
5
10, 1011, 1011101, 1011101111, 10111011111011, 101110111110111101, 10111011111011110110001, 1011101111101111011000110011, 101110111110111101100011001110111, 10111011111011110110001100111011111101
OFFSET
1,1
COMMENTS
Number of bits in a(n) = Sum_{i=1..n} A035100(i). See A328659(n).
LINKS
FORMULA
a(n) = CONCATENATE[i=1..n] A004676(i) = CONCATENATE[i=1..n] A007088(A000040(i)).
EXAMPLE
a(2) = 1011 = 10 Concat 11 = (2 base 2) Concat (3 base 2).
MAPLE
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
MATHEMATICA
With[{p = IntegerDigits[Prime[Range[15]], 2]}, Array[FromDigits[Flatten[p[[;; #]]]] &, Length[p]]] (* Paolo Xausa, Feb 26 2024 *)
PROG
(PARI) a(n) = fromdigits(concat(apply(binary, primes(n)))); \\ Michel Marcus, Jul 17 2023
CROSSREFS
KEYWORD
base,easy,nonn
AUTHOR
Jonathan Vos Post, Jan 14 2009
EXTENSIONS
Corrected terms a(6) and beyond from Seiichi Manyama, Jul 17 2023
STATUS
approved