A323415 Numbers equal to the carryless sum of their divisors.

1, 14, 84, 120, 1180, 1450, 10180, 12784, 100180, 101180, 114500, 139204, 1100180, 10000180, 10010180, 10111180, 11000180, 85937220, 101011180, 101101180, 101110180, 101111180, 110000180, 111001180, 111100180, 111101180, 111110180

Offset

1,2

Comments

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

Links

Table of n, a(n) for n=1..27.

Index entries for sequences related to carryless arithmetic

Example

For k = 14:
- the divisors of 14 are: 1, 2, 7, 14,
- the sum of the units are: 1 + 2 + 7 + 4 = 14 == 4 (mod 10),
- the sum of the tens are: 1,
- hence A323394(14) = 14 and 14 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)))); fromdigits(Vecrev(v), base)==n

Crossrefs

Cf. A323394.

Sequence in context: A250562 A166819 A108683 * A166389 A085036 A107935

Adjacent sequences: A323412 A323413 A323414 * A323416 A323417 A323418

Keyword

nonn,base

Author

Rémy Sigrist, Jan 13 2019

Status

approved