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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. 2
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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified September 26 20:36 EDT 2020. Contains 337374 sequences. (Running on oeis4.)