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A356981
Numbers k such that the sum of distinct digits of k equals the sum of the prime divisors of k.
1
2, 3, 5, 7, 84, 144, 160, 250, 343, 468, 735, 936, 975, 1125, 1215, 1375, 1408, 1600, 1694, 1872, 2401, 2500, 2646, 2880, 3920, 4913, 6084, 6318, 6860, 7296, 7695, 8624, 8704, 8788, 9126, 10125, 10240, 10816, 11264, 12672, 12675, 14641, 14896, 16000
OFFSET
1,1
COMMENTS
Similar to A070275, where distinctness of digits is not required.
EXAMPLE
144 = 2^4*3^2 and 1+4=2+3. Thus, 144 is in this sequence.
MATHEMATICA
Select[Range[2, 20000], Total[Union[IntegerDigits[#]]] == Total[Transpose[FactorInteger[#]][[1]]] &]
PROG
(Python)
from itertools import count, islice
from sympy import primefactors
def A356981_gen(startvalue=1): # generator of terms >= startvalue
return filter(lambda k:sum(int(d) for d in set(str(k)))==sum(primefactors(k)), count(max(startvalue, 1)))
A356981_list = list(islice(A356981_gen(), 30)) # Chai Wah Wu, Sep 12 2022
(PARI) isok(k) = vecsum(Set(digits(k))) == vecsum(factor(k)[, 1]); \\ Michel Marcus, Sep 12 2022
CROSSREFS
Sequence in context: A029976 A074310 A264576 * A070275 A171042 A068827
KEYWORD
nonn,base
AUTHOR
Tanya Khovanova, Sep 09 2022
STATUS
approved