

A097824


Gaps associated with the arithmetic progressions of semiprimes in A096003.


5



12, 12, 4, 52, 52, 72, 96, 198, 198, 114, 594, 48, 354, 1860, 3942, 2574, 2574, 2574, 20910, 20910, 9600, 9600, 152250, 152250, 152250, 152250, 1887270, 4667040, 4094790
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

4,1


COMMENTS

The terms a(1),a(2) and a(3) are omitted to avoid the ambiguity caused by the two progressions of length 3 ending at A096003(3)=14: a(3)=5 for (4,9,14) or a(3)=4 for (6,10,14).


LINKS

Table of n, a(n) for n=4..32.


EXAMPLE

a(6)=4 because the 6 semiprimes in the progression ending at A096003(6)=221 are separated by an increment of 4: 201=3*67, 205=5*41, 209=11*19, 213=3*71, 217=7*31, 221=13*17.


CROSSREFS

Cf. A096003, A093364 gaps in arithmetic progressions of primes, A082919 clusters of 8 consecutive semiprimes.
Sequence in context: A125509 A281251 A247511 * A133208 A118877 A112124
Adjacent sequences: A097821 A097822 A097823 * A097825 A097826 A097827


KEYWORD

more,nonn


AUTHOR

Hugo Pfoertner, Aug 27 2004


EXTENSIONS

a(26)a(30) from Hugo Pfoertner, Sep 07 2004
a(31)a(32) from Donovan Johnson, Jun 03 2012


STATUS

approved



