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A323414 Numbers whose carryless sum of divisors is zero. 1
87, 95, 540, 608, 973, 5940, 7906, 8787, 9595, 9715, 54540, 63796, 64648, 83337, 599940, 796677, 836169, 972223, 5459940, 6406408, 6441128, 6464648, 7165526, 8091755, 9514464, 54049140, 54599940, 64006408, 64064648, 64640648, 82913331 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Equivalently, numbers k such that A323394(k) = 0.

LINKS

Table of n, a(n) for n=1..31.

Index entries for sequences related to carryless arithmetic

EXAMPLE

For k = 87:

- the divisors of 87 are: 1, 3, 29, 87,

- the sum of units is: 1 + 3 + 9 + 7 = 20 == 0 (mod 10),

- the sum of tens is: 2 + 8 = 10 == 0 (mod 10),

- hence A323394(87) = 0 and 87 belongs to the sequence.

PROG

(PARI) isok(n, base=10) = my (v=[]); fordiv (n, d, my (w=Vecrev(digits(d, base))); v=vector(max(#v, #w), k, (if (k>#v, w[k], k>#w, v[k], (v[k]+w[k])%base)))); vecmax(v)==0

CROSSREFS

Cf. A323394.

Sequence in context: A295698 A095597 A095583 * A231403 A256083 A038005

Adjacent sequences:  A323411 A323412 A323413 * A323415 A323416 A323417

KEYWORD

nonn,base

AUTHOR

Rémy Sigrist, Jan 13 2019

STATUS

approved

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Last modified November 29 12:23 EST 2021. Contains 349416 sequences. (Running on oeis4.)