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%I #22 Dec 14 2023 19:38:43
%S 1,2,43,75,1186,16129,22171310,29231814,3730241915,4638312520,
%T 564739322621,675748403327,79685849413428,92806959504235,
%U 10693817060514336,121107948271615244,137122108958372625345,1541381231099684736354,1721551391241109785746455
%N Consider the triangle shown below; sequence contains the concatenation of numbers read at a 45-degree angle upwards with horizontal beginning with the first term of a row.
%C 1
%C 2 3
%C 4 5 6
%C 7 8 9 10
%C 11 12 13 14 15
%C 16 17 18 19 20 21
%C ...
%C a(n) also is the concatenation of the terms of the n-th row of A056536. - _Michel Marcus_, Dec 14 2023
%H G. C. Greubel, <a href="/A079823/b079823.txt">Table of n, a(n) for n = 1..395</a>
%p read("transforms"):
%p A079823aux := proc(n,k)
%p A000124(n)+k ;
%p end proc:
%p A079823 := proc(n)
%p local L,k,n0 ;
%p n0 := n-1 ;
%p L := [] ;
%p for k from 0 do
%p if k > n0-k then
%p break;
%p end if;
%p L := [op(L),A079823aux(n0-k,k)] ;
%p end do:
%p digcatL(L) ;
%p end proc: # _R. J. Mathar_, Aug 23 2012
%p # second Maple program:
%p T:= (i, j)-> i*(i-1)/2+j:
%p a:= n-> parse(cat(seq(T(n-j,j+1), j=0..(n-1)/2))):
%p seq(a(n), n=1..23); # _Alois P. Heinz_, Aug 03 2022
%t Table[FromDigits[Join@@IntegerDigits[Table[Binomial[n-k+1,2] + k, {k, Ceiling[n/2]}]]], {n,30}] (* _G. C. Greubel_, Dec 13 2023 *)
%Y Cf. A056536, A079824.
%K base,nonn
%O 1,2
%A _Amarnath Murthy_, Feb 11 2003
%E More terms from Jason D. W. Taff (jtaff(AT)jburroughs.org), Oct 31 2003
%E Corrected by _Philippe Deléham_, Feb 16 2004
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