The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A160649 a(1)=2. a(n) = a(n-1) + A001222(a(n-1)); where A001222(m) is the sum of prime-factorization exponents of m (or, A001222(m) is the number of primes dividing m, with multiplicity). 4

%I #20 Mar 01 2023 08:11:30

%S 2,3,4,6,8,11,12,15,17,18,21,23,24,28,31,32,37,38,40,44,47,48,53,54,

%T 58,60,64,70,73,74,76,79,80,85,87,89,90,94,96,102,105,108,113,114,117,

%U 120,125,128,135,139,140,144,150,154,157,158,160,166,168,173,174,177,179

%N a(1)=2. a(n) = a(n-1) + A001222(a(n-1)); where A001222(m) is the sum of prime-factorization exponents of m (or, A001222(m) is the number of primes dividing m, with multiplicity).

%C A001222(a(n)) = A160650(n) = a(n+1) - a(n).

%H G. C. Greubel, <a href="/A160649/b160649.txt">Table of n, a(n) for n = 1..10000</a>

%t NestList[# + PrimeOmega[#] &, 2, 100] (* _Zak Seidov_, Feb 15 2015 *)

%o (PARI) lista(nn) = {print1(a=2, ", "); for (n=2, nn, a += bigomega(a); print1(a, ", "););} \\ _Michel Marcus_, May 04 2018

%Y Cf. A001222, A094222, A160650.

%K nonn

%O 1,1

%A _Leroy Quet_, May 21 2009

%E Extended by _Ray Chandler_, Jun 16 2009

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 31 22:12 EDT 2024. Contains 373007 sequences. (Running on oeis4.)