|
| |
|
|
A116127
|
|
Number of numbers that are congruent to {2, 4} mod 6 between prime(n) and prime(n+1) inclusive.
|
|
1
| |
|
|
1, 1, 0, 2, 0, 2, 0, 2, 2, 0, 2, 2, 0, 2, 2, 2, 0, 2, 2, 0, 2, 2, 2, 2, 2, 0, 2, 0, 2, 4, 2, 2, 0, 4, 0, 2, 2, 2, 2, 2, 0, 4, 0, 2, 0, 4, 4, 2, 0, 2, 2, 0, 4, 2, 2, 2, 0, 2, 2, 0, 4, 4, 2, 0, 2, 4, 2, 4, 0, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 4, 0, 4, 0, 2, 2, 2, 2, 2, 0, 2, 4, 2, 2, 2, 2, 2, 4, 0, 6, 2, 4, 2, 2, 0, 2
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,4
|
|
|
COMMENTS
| For n > 2,
A001223(n) = 2 iff a(n) = 0,
A001223(n) = 4 or 6 or 8 iff a(n) = 2,
A001223(n) = 10 or 12 or 14 iff a(n) = 4,
A001223(n) = 16 or 18 or 20 iff a(n) = 6,
and so on. This can be generalized to
A001223(n) = 3*k-2 or 3*k or 3*k+2 iff a(n) = k for k >= 2.
|
|
|
PROG
| (MAGMA) [ #[ k: k in [NthPrime(n)..NthPrime(n+1)] | r eq 2 or r eq 4 where r is k mod 6 ]: n in [1..105] ]; /* Klaus Brockhaus, Apr 15 2007 */
|
|
|
CROSSREFS
| Cf. A000040 (primes), A001223 (differences between consecutive primes), A047235 (numbers congruent to {2, 4} mod 6).
Sequence in context: A096030 A025815 A029225 * A039979 A204173 A103668
Adjacent sequences: A116124 A116125 A116126 * A116128 A116129 A116130
|
|
|
KEYWORD
| nonn,easy
|
|
|
AUTHOR
| Giovanni Teofilatto (g.teofilatto(AT)tiscalinet.it), Apr 08 2007
|
|
|
EXTENSIONS
| Edited, corrected and extended by Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Apr 15 2007
|
| |
|
|
