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Concatenation of composite numbers between the n-th prime and the following prime.
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%I #13 Aug 14 2024 15:40:40

%S 4,6,8910,12,141516,18,202122,2425262728,30,3233343536,383940,42,

%T 444546,4849505152,5455565758,60,6263646566,686970,72,7475767778,

%U 808182,8485868788,90919293949596,9899100,102,104105106,108,110111112

%N Concatenation of composite numbers between the n-th prime and the following prime.

%H Andrew Howroyd, <a href="/A054264/b054264.txt">Table of n, a(n) for n = 2..1000</a>

%t FromDigits[Flatten[IntegerDigits/@(Range[#[[1]]+1,#[[2]]-1])]]&/@Partition[ Prime[Range[2,30]],2,1] (* _Harvey P. Dale_, Mar 04 2014 *)

%o (PARI) a(n)=my(r=prime(n)+1); fromdigits(concat(vector(nextprime(r)-r, i, digits(r+i-1)))) \\ _Andrew Howroyd_, Aug 14 2024

%Y Cf. A046933, A054265, A054266, A054267, A054268.

%K nonn,base,easy

%O 2,1

%A _Patrick De Geest_, Apr 15 2000

%E Offset changed and name edited by _Andrew Howroyd_, Aug 14 2024