

A050221


a(n) = number of sets of consecutive primes whose arithmetic mean is A060863(n).


4



1, 1, 1, 2, 1, 1, 2, 1, 3, 1, 3, 2, 2, 1, 1, 2, 2, 2, 2, 5, 2, 3, 2, 4, 2, 1, 3, 2, 1, 1, 2, 2, 1, 5, 1, 4, 2, 2, 1, 3, 1, 2, 1, 1, 4, 1, 2, 1, 1, 1, 1, 3, 2, 2, 2, 1, 1, 5, 3, 1, 1, 1, 2, 2, 2, 1, 1, 3, 3, 1, 4, 1, 2, 2, 1, 3, 3, 1, 3, 1, 2, 1, 1, 3, 1, 1, 1, 2, 1, 3, 1, 1, 1, 2, 3, 1, 1, 2, 4, 4, 2, 4, 1, 3, 2
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,4


COMMENTS

Essentially A122821 with the 0's removed.


LINKS

Table of n, a(n) for n=1..105.


FORMULA

a(n) = A122821(A060863(n)).


EXAMPLE

For n=4; A060863(4) = 5. the two sets are 5/1 = 5, (3+5+7)/3 = 5. so a(4)=2.


MATHEMATICA

f[n_]:=Block[{i=1, j, c=0, m}, While[Prime[i]<=n, j=1; While[m=Sum[Prime[k], {k, i, i+j1}]/j; If[m==n, c++ ]; m<n, j++ ]; i++ ]; c]; Select[Table[f[n], {n, 160}], #>0&] (* Ray Chandler, Oct 03 2006 *)


CROSSREFS

Cf. A060863, A122821.
Sequence in context: A247299 A127586 A055893 * A213235 A113279 A213234
Adjacent sequences: A050218 A050219 A050220 * A050222 A050223 A050224


KEYWORD

easy,nonn


AUTHOR

Naohiro Nomoto, May 08 2003


EXTENSIONS

Extended by Ray Chandler, Oct 03 2006


STATUS

approved



