login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A078445 Primes in A060620, i.e. primes which are integer parts of averages of initial primes. 2
2, 2, 3, 5, 11, 23, 29, 31, 53, 67, 79, 89, 97, 107, 149, 163, 223, 229, 241, 271, 277, 283, 307, 313, 347, 353, 373, 379, 401, 433, 443, 449, 479, 521, 541, 547, 557, 571, 601, 631, 659, 673, 683, 769, 797, 811, 821, 839, 853, 857, 881, 907, 953, 971, 1033, 1051 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

The sum of the reciprocals of the averages and integer parts of the averages both appear to converge. The difference between the two converges to 0.15971929...

FORMULA

Seq(n) = Floor((Sum(prime(x), x=1..k)/k) where k = 1, 2... prime(k) <= n

EXAMPLE

11 is in the sequence since average of first 10 primes is [(2+3+5+7+11+13+17+19+23+29)/10] = [119/10] = 11.

PROG

(PARI) \ moving average of the primes movavgp(p) = { ct=s=sr1=sr2=0; forprime(x=2, p, ct++; s+=x; y = floor(s/ct +.0); if(isprime(y), sr1+=1.0/y; sr2+=1.0/(s/ct); print1(y" "); ); ); print(); print(sr1" "sr2); print(); print(sr1-sr2); }

CROSSREFS

Cf. A060620.

Sequence in context: A058697 A030427 A049907 * A127166 A005426 A014644

Adjacent sequences:  A078442 A078443 A078444 * A078446 A078447 A078448

KEYWORD

easy,nonn

AUTHOR

Cino Hilliard (hillcino368(AT)gmail.com), Dec 31 2002

EXTENSIONS

Edited by Henry Bottomley (se16(AT)btinternet.com), Jan 02 2003

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 16 20:01 EST 2012. Contains 205955 sequences.