Treated as strings, the concatenation c of the prime factors of n, in increasing order, is an initial segment of n. Equivalently, n begins with c.
A069154
Treated as strings, the concatenation c of the prime factors of n, in increasing order, is an initial segment of n. Equivalently, n begins with c.
Terms
- a(0) =250a(1) =256a(2) =2048a(3) =2176a(4) =2304a(5) =2500a(6) =2560a(7) =2744a(8) =23328a(9) =25000a(10) =25600a(11) =119911a(12) =219488a(13) =236196a(14) =250000a(15) =256000a(16) =262144a(17) =290912a(18) =2097152a(19) =2238728a(20) =2317312a(21) =2359296a(22) =2370816a(23) =2500000a(24) =2560000a(25) =3515625a(26) =3720087a(27) =5117695a(28) =13436683a(29) =21359416
External references
- oeis: A069154