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First differences of A057809.
1

%I #12 Sep 01 2018 17:44:10

%S 2,2,2,19,3,3,63,4,20,210,5,5,10,5,5,648,72,12,24,6,6,6,1925,7,7,7,7,

%T 7,5314,16,16,16,8,8,15054,9,765,40240,40,30,10,30,40,10,10,10,110477,

%U 305655,12,144,12,12,12,12,12,12,12,204,60,12,36,12,12,12,12,823046,13

%N First differences of A057809.

%H Giovanni Resta, <a href="/A087238/b087238.txt">Table of n, a(n) for n = 2..1161</a>

%F a(n)=A057809(n+1)-A057809(n)

%e Large differences arise between max term in a cluster and least one in the next cluster of A057809. While small entries obtained as differences inside a cluster.

%e E.g.:...,21,6467079011,198,22,110,132,22,242,66,17541629593,23,... shows by first differences the transition from the 21st cluster to 23rd solution-set over the 22nd-set with multiples of 22.

%e First cluster is empty, while 11th contains one term (see A038227).

%t Differences[Select[Range[2,1500000],Divisible[#,PrimePi[#]]&]] (* _Harvey P. Dale_, Aug 13 2012 *)

%Y Cf. A038623-A038627, A057809, A087235-A087242.

%K nonn

%O 2,1

%A _Labos Elemer_, Sep 04 2003