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A120853
Triangle read by rows, where t(n,1) = 1, t(n,m) = t(n,m-1) + (largest nonprime {1 or composite} in row {n-1}).
2
1, 1, 2, 1, 2, 3, 1, 2, 3, 4, 1, 5, 9, 13, 17, 1, 10, 19, 28, 37, 46, 1, 47, 93, 139, 185, 231, 277, 1, 232, 463, 694, 925, 1156, 1387, 1618, 1, 1619, 3237, 4855, 6473, 8091, 9709, 11327, 12945, 1, 12946, 25891, 38836, 51781, 64726, 77671, 90616, 103561, 116506
OFFSET
1,3
EXAMPLE
9 is the largest composite in row 5 of the triangle. So t(6,m) = 1 + 9*(m-1), for 1 <=m <=6.
PROG
(PARI) {z=10; w=[]; for(n=1, z, k=0; for(j=1, #w, if(k<w[j]&&(w[j]==1||!isprime(w[j])), k=w[j])); print1(a=1, ", "); w=[a]; for(m=2, n, a=k+a; print1(a, ", "); w=concat(w, a)))} - (Klaus Brockhaus, Aug 17 2006)
CROSSREFS
Cf. A120852.
Row sums are in A160965. [From Klaus Brockhaus, May 31 2009]
Sequence in context: A194973 A195113 A120418 * A175022 A243613 A194844
KEYWORD
nonn,tabl
AUTHOR
Leroy Quet, Jul 08 2006
EXTENSIONS
More terms from Klaus Brockhaus, Aug 17 2006
STATUS
approved