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A082221
Main diagonal of array A082218.
5
1, 7, 13, 29, 43, 67, 82, 100, 139, 149, 240, 160, 270, 340, 373, 427, 426, 438, 579, 793, 505, 679, 877, 1037, 820, 994, 1240, 1268, 1221, 1109, 1369, 1487, 1800, 1678, 1745, 1607, 2406, 2042, 2560, 2356, 2701, 2407, 2625, 3127, 2791, 2971, 3210, 3170, 3642
OFFSET
1,2
PROG
(PARI) lista(nn) = { my(a=matrix(nn, nn)); S=Set();
for(s=2, nn+1, if(s%2, i0=1; i1=s-1; i2=1, i0=s-1; i1=1; i2=-1);
forstep(i=i0, i1, i2, j=s-i;
ii=sum(k=1, j-1, a[i, k]); jj=sum(k=1, i-1, a[k, j]);
c=chinese(Mod(ii, j), Mod(jj, i));
t=component(c, 1)-lift(c); while(setsearch(S, t), t+=component(c, 1));
a[i, j]=t; S=setunion(S, [t]);
if(i==j, print1(", ", sum(k=1, j, a[i, j])/j) ); ))} \\ This is a modification of Max Alekseyev's PARI program from A082219. - Petros Hadjicostas, Feb 25 2021
CROSSREFS
KEYWORD
nonn
AUTHOR
Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Apr 09 2003
EXTENSIONS
More terms from Max Alekseyev, Jun 08 2007
Edited by N. J. A. Sloane, Jun 11 2007
Name edited by Petros Hadjicostas, Feb 25 2021
STATUS
approved