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A359075
Numbers that do not have two divisors with an equal sum of digits.
2
1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 13, 14, 15, 16, 17, 19, 23, 25, 26, 28, 29, 31, 32, 33, 34, 35, 37, 38, 39, 41, 43, 46, 47, 49, 51, 53, 55, 56, 57, 58, 59, 61, 62, 64, 65, 67, 68, 69, 71, 73, 74, 75, 76, 77, 78, 79, 82, 83, 85, 86, 87, 89, 91, 92, 93, 94, 95, 97
OFFSET
1,2
MATHEMATICA
a={}; For[k=1, k<=97, k++, If[Length[Intersection[Table[Total[Part[IntegerDigits[Divisors[k]], i]], {i, DivisorSigma[0, k]}]]] == DivisorSigma[0, k], AppendTo[a, k]]]; a
PROG
(Python)
from sympy import divisors
def sod(n): return sum(map(int, str(n)))
def ok(n):
s = set()
for d in divisors(n, generator=True):
sd = sod(d)
if sd in s: return False
s.add(sd)
return True
print([k for k in range(1, 98) if ok(k)]) # Michael S. Branicky, Dec 15 2022
(PARI) isok(k) = my(d=divisors(k)); #Set(apply(sumdigits, d)) == #d; \\ Michel Marcus, Dec 19 2022
CROSSREFS
Complement of A359074.
Cf. A000005, A007953, A359077 (proper divisors).
Sequence in context: A267215 A039219 A038365 * A247761 A031185 A342441
KEYWORD
nonn,base
AUTHOR
Stefano Spezia, Dec 15 2022
STATUS
approved