

A081491


Triangle read by rows in which the nth row contains n terms of an arithmetic progression with a common difference of (n1) and the first term of (n+1)th row is 1 more than the last term of the nth row.


3



1, 2, 3, 4, 6, 8, 9, 12, 15, 18, 19, 23, 27, 31, 35, 36, 41, 46, 51, 56, 61, 62, 68, 74, 80, 86, 92, 98, 99, 106, 113, 120, 127, 134, 141, 148, 149, 157, 165, 173, 181, 189, 197, 205, 213, 214, 223, 232, 241, 250, 259, 268, 277, 286, 295, 296, 306, 316, 326, 336, 346
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OFFSET

1,2


LINKS

Table of n, a(n) for n=1..61.


EXAMPLE

1; 2,3; 4,6,8; 9,12,15,18; 19,23,27,31,35; 36,41,46,51,56,61; ...


CROSSREFS

Cf. A002522, A005408, A081489, A081490, A081492.
Sequence in context: A261342 A002348 A019469 * A048716 A010434 A074230
Adjacent sequences: A081488 A081489 A081490 * A081492 A081493 A081494


KEYWORD

nonn,tabl


AUTHOR

Amarnath Murthy, Mar 25 2003


EXTENSIONS

More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 29 2003


STATUS

approved



