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A082226
First column of array A082224.
6
1, 3, 4, 7, 5, 13, 9, 21, 11, 17, 19, 23, 25, 27, 29, 31, 33, 37, 35, 41, 39, 43, 45, 47, 49, 51, 53, 57, 55, 59, 61, 65, 63, 67, 69, 71, 73, 77, 75, 79, 81, 85, 83, 87, 89, 91, 93, 97, 95, 99, 101, 105, 103, 107, 109, 111, 113, 115, 117, 119, 121, 125, 123, 127, 129, 131
OFFSET
1,2
COMMENTS
If instead we read all the antidiagonals downwards, we get A005408 as the first column.
PROG
(PARI) lista(nn) = { my(A=matrix(nn, nn)); S=Set(); for(s=2, nn+1, for(i=1, s-1, if(s%2, q=[i, s-i], q=[s-i, i]); p=[sum(j=1, q[2]-1, A[q[1], j]), sum(j=1, q[1]-1, A[j, q[2]])]; n=1; while(setsearch(S, n) || (p[1]&&!isprime(p[1]+n)) || (p[2]&&isprime(p[2]+n)), n++); A[q[1], q[2]]=n; S=setunion(S, Set([n])); if(q[2]==1, print1(n, ", ")); )) } /* This is a modification of the PARI program by Max Alekseyev in A082228. - Petros Hadjicostas, Feb 25 2021 */
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Amarnath Murthy, Apr 09 2003
EXTENSIONS
Edited and extended David Wasserman, Feb 27 2006
STATUS
approved