A322828 a(n) is the concatenation of n and pi(n).

10, 21, 32, 42, 53, 63, 74, 84, 94, 104, 115, 125, 136, 146, 156, 166, 177, 187, 198, 208, 218, 228, 239, 249, 259, 269, 279, 289, 2910, 3010, 3111, 3211, 3311, 3411, 3511, 3611, 3712, 3812, 3912, 4012, 4113, 4213, 4314, 4414, 4514, 4614, 4715, 4815, 4915, 5015, 5115

Offset

1,1

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Chris K. Caldwell and G. L. Honaker, Jr., Prime Curios! 1027569834

Example

a(5) = 53 because if n=5 then pi(5)=3, therefore concatenation gives 53.

Maple

a:= n-> parse(cat(n, numtheory[pi](n))):
seq(a(n), n=1..60);  # Alois P. Heinz, Dec 28 2018

Prog

(PARI) a(n) = eval(concat(Str(n), Str(primepi(n)))); \\ Michel Marcus, Dec 29 2018

Crossrefs

Cf. A000027, A000720, A045532.

Sequence in context: A042871 A041192 A061231 * A104341 A098954 A346261

Adjacent sequences: A322825 A322826 A322827 * A322829 A322830 A322831

Keyword

nonn,base

Author

G. L. Honaker, Jr., Dec 26 2018

Status

approved