At the start of the U2 song Vertigo, Bono clearly sings these words. Now to me that means 1, 2, 3, 14.

So do you think that with all the work Bono has done for comic relief and Live Aid that there actually might not be a problem in Africa and that perhaps Bono just lost count?

Source:Resolved Question: Unos, Dos, Tres, Quatores,….?

BOSTON - Tom Petty and the Heartbreakers rocked a sold-out Garden to the rafters Friday night without a whiff of U2’s pomp, Stonesian swagger, or the Red Hot Chili Peppers’ raw energy - just first-class, meat-and-potatoes anthems from one of the finest live bands in America.

Source:Petty rocks Garden with his hit list (Worcester Telegram & Gazette)

Given that:

Arithmetic Progression:
U1=a ,
U2=a+d ,
U3=a+2d ,
U4=a+3d ,
…
Un=a+(n-1)d

and Un=[ Un-1 + Un+1 ] / 2

Geometric Progression:
U1=a ,
U2=ar ,
U3=ar^2 ,
U4=ar^3 ,
…
Un=ar^(n-1)

and Un=sqrt[ Un-1 x Un+1 ]

Arithmetic-Geometric Progression:
U1=a ,
U2=(a+d)r ,
U3=(a+2d)r^2 ,
U4=(a+3d)r^3 ,
…
Un=[ a+(n-1)d ] r^(n-1)

and Un=[ r Un-1 + Un+1 / r ] / 2

My question is is there a formula for obtaining Un (for an AGP) by just using Un-1 and Un+1 without having to find r , or is it impossible ?

Thanks.

Source:Open Question: Maths Question about Arithmetic-Geometric Progressions…?

Source:Open Question: U2: dont you guys think they should do something like "The Joshua Tree" or "Achtung Baby" again?

The British alt rock band comes out with its much anticipated 4th album Tuesday.

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