A097824 Gaps associated with the arithmetic progressions of semiprimes in A096003.

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

Offset: 4

Author

Hugo Pfoertner, Aug 27 2004

Keywords

• more
• nonn

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).

Examples

			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.

Extensions

a(26)-a(30) from Hugo Pfoertner, Sep 07 2004

a(31)-a(32) from Donovan Johnson, Jun 03 2012