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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.
3

%I #14 Jan 22 2020 02:44:22

%S 1,3,42,105,1196,21128,2220137,36231914,3735241815,5538342517,

%T 565439332616,785753403227,79775852413128,105807659514230,

%U 106104817560504329,1361071038274614944

%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 3 2

%C 4 5 6

%C 10 9 8 7

%C 11 12 13 14 15

%C 21 20 19 18 17 16

%C 22 23 24 25 26 27 28

%C 36 35 34 33 32 31 30 29

%C 37 38 39 40 41 42 43 44 45

%C 55 54 53 52 51 50 49 48 47 46

%C 56 57 58 59 60 61 62 63 64 65 66

%p read("transforms") ;

%p A079826 := proc(n)

%p local L, k;

%p L := [] ;

%p for k from 1 to (n+1)/2 do

%p L := [op(L),A056011(n-k+1,k)] ;

%p end do:

%p digcatL(L) ;

%p end proc: # _R. J. Mathar_, Sep 05 2012

%Y Cf. A079825, A056011.

%K base,easy,nonn

%O 1,2

%A _Amarnath Murthy_, Feb 11 2003

%E More terms from Jonathan R. Love (japanada11(AT)yahoo.ca), Mar 08 2007

%E Corrected by _Kevin Ryde_, Aug 23 2012