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A358671
Numbers k such that for all factorizations of k as x*y, the sum x+y is carryfree when the addition is done in the primorial base, A049345.
3
2, 4, 6, 14, 18, 24, 26, 28, 38, 42, 52, 54, 62, 72, 74, 76, 78, 86, 96, 98, 114, 122, 124, 126, 134, 146, 148, 158, 172, 186, 194, 206, 218, 222, 244, 254, 258, 268, 278, 292, 302, 314, 316, 326, 362, 366, 386, 388, 398, 402, 412, 422, 434, 436, 438, 446, 458, 474, 482, 508, 518, 542, 554, 556, 558
OFFSET
1,1
COMMENTS
Numbers k such that there are no factorization of k into such a pair of natural numbers x and y that would generate any carries when added together in the primorial base.
FORMULA
{k | A358233(k) = A038548(k)}.
EXAMPLE
8 is not included, because while factorization 1*8 would yield a carry-free sum ("1" and "110" added together gives "111" = 9 in primorial base, A049345), factorization 2*4 would not, as 2+4 (= "10" + "20") and 2 is the max. allowed digit in the second rightmost place.
PROG
(PARI) isA358671(n) = A358670(n);
CROSSREFS
Cf. A038548, A049345, A276086, A329041, A358233, A358670 (characteristic function).
Cf. also A358673.
Sequence in context: A138307 A323101 A124693 * A095698 A277909 A064409
KEYWORD
nonn,base
AUTHOR
Antti Karttunen, Nov 26 2022
STATUS
approved