A119603 Merging prime factors of n-th composite number.

22, 23, 222, 33, 25, 223, 27, 35, 2222, 233, 225, 37, 211, 2223, 55, 213, 333, 227, 235, 22222, 311, 217, 57, 2233, 219, 313, 2225, 237, 2211, 335, 223, 22223, 77, 255, 317, 2213, 2333, 511, 2227, 319, 229, 2235, 231, 337, 222222, 513, 2311, 2217, 323, 257

Offset

1,1

Comments

Rule "replace n-th composite number by concatenation of its prime factors" in A037271; composite numbers A002808.

Links

Table of n, a(n) for n=1..50.

Example

a(6)=223 because 6th composite number is 12: A002808(6)=12, then 12=2*2*3 and merging prime factors we get a(6)=223.

Mathematica

Sow[FromDigits@Flatten[Table[IntegerDigits[ #[[1]]], {#[[2]]}]&/@FactorInteger@(n)]]], {n, 2, 115}]][[2, 1]]

Crossrefs

Cf. A002808, A037271.

Sequence in context: A041998 A042000 A042002 * A042004 A042006 A042008

Adjacent sequences: A119600 A119601 A119602 * A119604 A119605 A119606

Keyword

nonn,base

Author

Zak Seidov, Jun 03 2006

Status

approved