A068865 a(1) = 1; a(n) is the smallest triangular number not already in the sequence which differs from a(n-1) at every digit.

1, 3, 6, 10, 21, 15, 28, 36, 45, 66, 55, 78, 91, 105, 210, 136, 253, 120, 231, 153, 276, 190, 325, 171, 300, 435, 351, 406, 378, 465, 528, 496, 561, 630, 595, 666, 703, 820, 741, 903, 780, 861, 946, 1035, 990, 1081, 2145, 1326, 2080, 1128, 2016, 1225, 2346

Offset

1,2

Links

Table of n, a(n) for n=1..53.

Example

136 follows 210 as the smallest triangular number not included earlier and differing at every digit position with 210.

Crossrefs

Cf. A000217, A068855.

Sequence in context: A365694 A122628 A343386 * A060179 A056411 A068855

Adjacent sequences: A068862 A068863 A068864 * A068866 A068867 A068868

Keyword

nonn,base

Author

Amarnath Murthy, Mar 13 2002

Extensions

Corrected and extended by Sascha Kurz, Feb 02 2003

Status

approved