

A075652


Triangle read by rows in which the nth row is an arithmetic progression of n terms with a common difference of n, and the first term is chosen the lowest possible so that no number appears twice.


5



1, 2, 4, 3, 6, 9, 7, 11, 15, 19, 8, 13, 18, 23, 28, 14, 20, 26, 32, 38, 44, 22, 29, 36, 43, 50, 57, 64, 31, 39, 47, 55, 63, 71, 79, 87, 40, 49, 58, 67, 76, 85, 94, 103, 112, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 82, 93, 104, 115, 126, 137, 148, 159, 170, 181, 192, 83
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OFFSET

1,2


LINKS

Ivan Neretin, Table of n, a(n) for n = 1..5050


EXAMPLE

Triangle starts:
1;
2, 4;
3, 6, 9;
7, 11, 15, 19;
8, 13, 18, 23, 28;
14, 20, 26, 32, 38, 44;
22, 29, 36, 43, 50, 57, 64;
...


MATHEMATICA

a = {1}; Do[d = Range[0, n  1]*n; a = Join[a, Min[Complement[Range[Max@a + 1], Flatten@Outer[Plus, a, d]]] + d], {n, 2, 12}]; a (* Ivan Neretin, Nov 09 2016 *)


CROSSREFS

Cf. A075648, A075649, A075650, A075651.
Sequence in context: A246278 A246366 A271865 * A331018 A054428 A095167
Adjacent sequences: A075649 A075650 A075651 * A075653 A075654 A075655


KEYWORD

nonn,tabl


AUTHOR

Amarnath Murthy, Oct 01 2002


EXTENSIONS

More terms from David Wasserman, Jan 22 2005


STATUS

approved



