A259849 - OEIS

%I #37 Aug 28 2015 17:26:14

%S 17,262,4312,16779232,4311709696,73014280192,1152921572789321728,

%T 1329227995784915873480267812046897152,

%U 95780971304118054976624684827067691392844968751005696

%N Average of consecutive pairs of perfect numbers.

%C Assuming that no odd perfect number exists.

%F a(n) = (A000396(n)+A000396(n+1))/2, assuming there are no odd perfect numbers.

%e a(1) = (6 + 28)/2 = 17.

%p perf:= n -> numtheory:-mersenne([n])*(numtheory:-mersenne([n])+1)/2:

%p seq((perf(n)+perf(n+1))/2, n=1..15); # _Robert Israel_, Aug 20 2015

%Y Cf. A000396.

%K nonn

%O 1,1

%A _José de Jesús Camacho Medina_, Aug 17 2015