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 A139083 a(n) = (smallest prime-power among the largest powers of each prime dividing n) + (smallest prime-power among the largest powers of each prime dividing (n+1)). 2

%I

%S 3,5,7,9,7,9,15,17,11,13,14,16,15,5,19,33,19,21,23,7,5,25,26,28,27,29,

%T 31,33,31,33,63,35,5,7,9,41,39,5,8,46,43,45,47,9,7,49,50,52,51,5,7,57,

%U 55,7,12,10,5,61,62,64,63,9,71,69,7,69,71,7,5,73,79,81,75,5,7,11,9,81

%N a(n) = (smallest prime-power among the largest powers of each prime dividing n) + (smallest prime-power among the largest powers of each prime dividing (n+1)).

%C The largest powers of each prime dividing 44 are 2^2 and 11^1. The least of these is 2^2 =4. The largest powers of each prime dividing 45 are 3^2 and 5^1. The least of these is 5^1 = 5. So a(44) = 4 + 5 = 9.

%F a(n) = A034684(n) + A034684(n+1) [From _Franklin T. Adams-Watters_, Apr 09 2009]

%o Contribution from _Franklin T. Adams-Watters_, Apr 09 2009: (Start)

%o (PARI) minpp(n)=local(m,r,pp);if(n==1,1,m=factor(n);r=m[1,1]^m[1,2];for(i=2,matsize(m)[1],pp=m[i,1]^m[i,2];if(pp<r,r=pp));r)

%o vector(80,i,minpp(i)+minpp(i+1)) (End)

%Y Cf. A139081, A139084.

%K nonn

%O 1,1

%A _Leroy Quet_, Apr 07 2008

%E More terms from _Franklin T. Adams-Watters_, Apr 09 2009

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Last modified July 2 10:07 EDT 2022. Contains 355004 sequences. (Running on oeis4.)