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%I #15 Mar 08 2022 15:42:48
%S 3,4,3,6,6,3,5,9,8,3,6,12,4,12,3,7,15,12,3,5,7,10,18,14,3,9,21,4,8,20,
%T 3,6,12,24,18,3,5,9,15,27,20,3,6,9,15,30,4,10,28,3,13,33,24,3,5,7,10,
%U 14,20,36,6,30,3,15,39,4,12,36,3,6,11,21,42,30,3,5,8,11,16,25,45
%N Irregular array read by rows: row n contains the sums of each pair of consecutive positive divisors of n.
%C The first listed row is row 2. Row n contains d(n)-1 terms, where d(n) is the number of positive divisors of n.
%H Harvey P. Dale, <a href="/A136195/b136195.txt">Table of n, a(n) for n = 2..1000</a>
%e The positive divisors of 20 are 1,2,4,5,10,20. 1+2=3. 2+4=6. 4+5=9. 5+10=15. 10+20=30. So row 20 is (3,6,9,15,30).
%p with(numtheory): a:=proc(n) local dn: dn:=divisors(n): seq(dn[i]+dn[i+1],i= 1..nops(dn)-1) end proc: for n from 2 to 30 do a(n) end do; # _Emeric Deutsch_, Jan 05 2008
%t Table[Total/@Partition[Divisors[n],2,1],{n,30}]//Flatten (* _Harvey P. Dale_, Mar 08 2022 *)
%Y Cf. A136193, A032741 (row lengths).
%K nonn,tabf
%O 2,1
%A _Leroy Quet_, Dec 20 2007
%E More terms from _Emeric Deutsch_, Jan 05 2008
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