A109448 Numbers n such that the concatenation of consecutive increasing numbers beginning with Harshad(n) and ending with Harshad(n+1) is a Harshad number; or n such that A112131(n) is a Harshad number.

1, 4, 9, 10, 21, 45, 48, 100, 102, 135, 144, 201, 228, 315, 320, 378, 399, 408, 736, 792, 803, 820, 832, 1000, 1035, 1044, 1056, 1088, 1101, 1128, 1215, 1233, 1308, 1431, 1720, 1908, 1926, 1962, 2001, 2028, 2052, 2119, 2208, 2210, 2223, 2241, 2618, 2620

Offset

1,2

Links

Table of n, a(n) for n=1..48.

Example

a(5)=21 because 2+1+2+2+2+3+2+4 = 18 and 21222324/18 = 1179018.

Crossrefs

Cf. A005349.

Sequence in context: A098144 A109412 A061766 * A177927 A062398 A030754

Adjacent sequences: A109445 A109446 A109447 * A109449 A109450 A109451

Keyword

base,nonn

Author

Jason Earls, Aug 27 2005

Status

approved