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A048795
Concatenate p p times, where p runs through the primes.
0
22, 333, 55555, 7777777, 1111111111111111111111, 13131313131313131313131313, 1717171717171717171717171717171717, 19191919191919191919191919191919191919, 2323232323232323232323232323232323232323232323
OFFSET
1,1
FORMULA
log a(n) ~ (log 10)n log n. - Charles R Greathouse IV, Sep 20 2012
EXAMPLE
For each prime number p we write down 'p' p times.
2 -> 22
3 -> 333
5 -> 55555
... -> ...
MAPLE
a:= n-> (p-> parse(cat(p$p)))(ithprime(n)):
seq(a(n), n=1..10); # Alois P. Heinz, Jul 07 2016
MATHEMATICA
Table[FromDigits[Flatten[IntegerDigits/@PadRight[{}, p, p]]], {p, Prime[Range[10]]}] (* Harvey P. Dale, Jul 07 2022 *)
PROG
(PARI) a(n) = {p = prime(n); s = Str(p); ss = ""; for (k=1, p, ss = concat(ss, s); ); eval(ss); } \\ Michel Marcus, Jul 02 2016
CROSSREFS
Sequence in context: A053422 A000461 A216730 * A068186 A021284 A019623
KEYWORD
nonn,base,easy
AUTHOR
Patrick De Geest, Jul 15 1999
STATUS
approved