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A366965
Numbers whose difference between the largest and smallest digits is equal to 8.
9
19, 80, 91, 108, 119, 129, 139, 149, 159, 169, 179, 180, 189, 191, 192, 193, 194, 195, 196, 197, 198, 199, 208, 219, 280, 291, 308, 319, 380, 391, 408, 419, 480, 491, 508, 519, 580, 591, 608, 619, 680, 691, 708, 719, 780, 791, 800, 801, 802, 803, 804, 805, 806, 807, 808, 810
OFFSET
1,1
COMMENTS
The number of n-digit terms of this sequence is 17*9^(n-1) - 31*8^(n-1) + 2*7^n.
MATHEMATICA
Select[Range[810], Max[d=IntegerDigits[#]]-Min[d]==8 &]
PROG
(Python)
def ok(n): return max(d:=list(map(int, str(n))))-min(d) == 8
print([k for k in range(900) if ok(k)]) # Michael S. Branicky, Oct 30 2023
(PARI) isok(n) = my(d=digits(n)); vecmax(d) - vecmin(d) == 8; \\ Michel Marcus, Nov 05 2023
CROSSREFS
Cf. A037904.
Cf. A010785 (difference = 0), A366958 (difference = 1), A366959 (difference = 2), A366960 (difference = 3), A366961 (difference = 4), A366962 (difference = 5), A366963 (difference = 6), A366964 (difference = 7), A366966 (difference = 9).
Sequence in context: A127270 A053665 A050522 * A172973 A212056 A290224
KEYWORD
nonn,base,easy
AUTHOR
Stefano Spezia, Oct 30 2023
STATUS
approved