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A241989 Positive numbers n that are divisible by the sum of the digits of n in base 16. 2
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 18, 20, 30, 32, 33, 35, 36, 40, 45, 48, 50, 54, 60, 64, 65, 66, 70, 72, 75, 80, 90, 96, 99, 100, 105, 108, 112, 120, 126, 128, 130, 132, 135, 140, 144, 150, 160, 165, 175, 176, 180, 192, 195, 198, 200 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

A base 16 version of Harshad (or Niven) numbers (A005349).

Numbers n such that n = 0 modulo A053836(n). - Antti Karttunen, Aug 22 2014

LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..10000

EXAMPLE

82478 is in the sequence as it is 1422E in hexadecimal and 1+4+2+2+14 = 23 which divides 82478.

MATHEMATICA

Select[Range[200], Divisible[#, Total@ IntegerDigits[#, 16]] &] (* Indranil Ghosh, Jun 12 2017 *)

PROG

(Python)

from gmpy2 import digits

A241989 = [n for n in range(1, 10**3) if not n % sum([int(d, 16) for d in digits(n, 16)])]

(MIT/GNU Scheme, with Antti Karttunen's IntSeq-library)

(define A241989 (MATCHING-POS 1 1 (lambda (n) (zero? (modulo n (A053836 n))))))

(define (A053836 n) (let loop ((n n) (i 0)) (if (zero? n) i (loop (floor->exact (/ n 16)) (+ i (modulo n 16))))))

CROSSREFS

Cf. A005349, A053836, A245802.

Sequence in context: A246076 A246082 A060340 * A246089 A078510 A246100

Adjacent sequences:  A241986 A241987 A241988 * A241990 A241991 A241992

KEYWORD

nonn,base

AUTHOR

Chai Wah Wu, Aug 22 2014

STATUS

approved

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Last modified October 18 13:31 EDT 2019. Contains 328161 sequences. (Running on oeis4.)