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A054264
Concatenation of composite numbers between the n-th prime and the following prime.
5
4, 6, 8910, 12, 141516, 18, 202122, 2425262728, 30, 3233343536, 383940, 42, 444546, 4849505152, 5455565758, 60, 6263646566, 686970, 72, 7475767778, 808182, 8485868788, 90919293949596, 9899100, 102, 104105106, 108, 110111112
OFFSET
2,1
LINKS
MATHEMATICA
FromDigits[Flatten[IntegerDigits/@(Range[#[[1]]+1, #[[2]]-1])]]&/@Partition[ Prime[Range[2, 30]], 2, 1] (* Harvey P. Dale, Mar 04 2014 *)
PROG
(PARI) a(n)=my(r=prime(n)+1); fromdigits(concat(vector(nextprime(r)-r, i, digits(r+i-1)))) \\ Andrew Howroyd, Aug 14 2024
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Patrick De Geest, Apr 15 2000
EXTENSIONS
Offset changed and name edited by Andrew Howroyd, Aug 14 2024
STATUS
approved