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A061120 Compute sum of divisors of the prime(n+1)-prime(n)-1 composite numbers between two consecutive primes; choose the smallest. 2

%I

%S 7,12,13,28,24,39,32,31,72,48,56,96,72,57,72,168,84,96,195,96,121,108,

%T 112,156,216,162,280,152,133,176,160,288,168,372,192,192,252,183,240,

%U 546,216,508,294,468,240,252,342,560,384,288,744,280,288,304,324,720

%N Compute sum of divisors of the prime(n+1)-prime(n)-1 composite numbers between two consecutive primes; choose the smallest.

%H Harry J. Smith, <a href="/A061120/b061120.txt">Table of n, a(n) for n = 0..1000</a>

%F a(n) = Min{sigma(c); p(n+1) > c > p(n)}, c is composite, p(n) is the n-th prime and sigma=A000203().

%o (PARI) { n=-1; q=3; m=10^6; forprime (p=5, prime(1003), a=m; for (i=q + 1, p - 1, a=min(sigma(i), a)); q=p; write("b061120.txt", n++, " ", a) ) } \\ _Harry J. Smith_, Jul 18 2009

%Y Cf. A000203, A061141.

%K nonn

%O 0,1

%A _Labos Elemer_, May 29 2001

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Last modified November 22 03:40 EST 2019. Contains 329386 sequences. (Running on oeis4.)