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%I #9 Jun 12 2021 12:53:08
%S 1,113,111336,1111333670,111113333667115,111111333336667111671,
%T 1111111333333666671111667338,111111113333333666667111116667334116,
%U 111111111333333336666667111111666673334112005,1111111111333333333666666671111111666667333341112001005
%N Partial sums of A180039.
%C Row 5 of the Pascal array expressed as triangular numbers in 2 ways (value and number of digits). Could be viewed as part of a group expressing the n-th row of the Pascal array in n ways (see example).
%e For the fifth row of the Pascal array, n=5:
%e 1,5,15,..
%e 1,14,150,..
%e 1,113,111336,..
%e 1,1112,1111112223,..
%e 1,11111,111111111111111,..
%e For n=4:
%e 1,4,10,20,..
%e 1,13,136,1370,..
%e 1,112,111223,1111222334,..
%e 1,1111,1111111111,11111111111111111111,..
%t Accumulate[Accumulate[Table[FromDigits[PadRight[{},n,1]],{n,Accumulate[ Range[10]]}]]] (* _Harvey P. Dale_, Jun 12 2021 *)
%Y Cf. A007318, A052262, A180039.
%K nonn
%O 1,2
%A _Mark Dols_, Aug 08 2010
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