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A222405 Triangle read by rows: left and right edges are A002061 (1,3,7,13,21,...), interior entries are filled in using the Pascal triangle rule. 4

%I #8 Jan 14 2014 10:03:36

%S 1,3,3,7,6,7,13,13,13,13,21,26,26,26,21,31,47,52,52,47,31,43,78,99,

%T 104,99,78,43,57,121,177,203,203,177,121,57,73,178,298,380,406,380,

%U 298,178,73,91,251,476,678,786,786,678,476,251,91,111,342,727,1154,1464,1572,1464,1154,727,342,111

%N Triangle read by rows: left and right edges are A002061 (1,3,7,13,21,...), interior entries are filled in using the Pascal triangle rule.

%e Triangle begins:

%e 1

%e 3, 3

%e 7, 6, 7

%e 13, 13, 13, 13

%e 21, 26, 26, 26, 21

%e 31, 47, 52, 52, 47, 31

%e 43, 78, 99, 104, 99, 78, 43

%e 57, 121, 177, 203, 203, 177, 121, 57

%e 73, 178, 298, 380, 406, 380, 298, 178, 73

%e ...

%p d:=[seq(n*(n+1)+1,n=0..14)];

%p f:=proc(d) local T,M,n,i;

%p M:=nops(d);

%p T:=Array(0..M-1,0..M-1);

%p for n from 0 to M-1 do T[n,0]:=d[n+1]; T[n,n]:=d[n+1]; od:

%p for n from 2 to M-1 do

%p for i from 1 to n-1 do T[n,i]:=T[n-1,i-1]+T[n-1,i]; od: od:

%p lprint("triangle:");

%p for n from 0 to M-1 do lprint(seq(T[n,i],i=0..n)); od:

%p lprint("row sums:");

%p lprint([seq( add(T[i,j],j=0..i), i=0..M-1)]);

%p end;

%p f(d);

%t t[n_, n_] := n^2+n+1; t[n_, 0] := n^2+n+1; t[n_, k_] := t[n, k] = t[n-1, k-1] + t[n-1, k]; Table[t[n, k], {n, 0, 10}, {k, 0, n}] // Flatten (* _Jean-François Alcover_, Jan 14 2014 *)

%Y Cf. A007318, A002061, A222403, A222404.

%Y Row sums are A027178.

%K nonn,tabl

%O 0,2

%A _N. J. A. Sloane_, Feb 18 2013

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Last modified September 14 15:15 EDT 2024. Contains 375921 sequences. (Running on oeis4.)