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A061381
Smallest "inconsummate number" in base n greater than in the previous base.
1
13, 17, 29, 46, 64, 86, 105, 136, 161, 200, 229, 276, 309, 362, 419, 460, 505, 572, 621, 694, 749, 830, 889, 978, 1054, 1136, 1205, 1306, 1381, 1490, 1569, 1684, 1769, 1892, 1999, 2112, 2205, 2342, 2441, 2584, 2689, 2840, 2949, 3106, 3269, 3386, 3505, 3678
OFFSET
2,1
LINKS
MATHEMATICA
n = 1; Do[ While[k = n; While[ Apply[ Plus, IntegerDigits[k, b] ]*n != k && k < 100n, k += n]; k != 100n, n++ ]; Print[n], {b, 2, 60} ]
PROG
(Python)
from functools import lru_cache
from itertools import count, combinations_with_replacement
from sympy.ntheory import digits
@lru_cache(maxsize=None)
def A061381(n):
for k in count((0 if n <= 2 else A061381(n-1))+1):
for l in count(1):
if (n-1)*l*k < n**(l-1):
return k
for d in combinations_with_replacement(range(n), l):
if (s:=sum(d)) > 0 and sorted(digits(s*k, n)[1:]) == list(d):
break
else:
continue
break # Chai Wah Wu, May 09 2023
CROSSREFS
Cf. A052491.
Sequence in context: A079348 A349667 A174024 * A048520 A283407 A283358
KEYWORD
base,easy,nice,nonn
AUTHOR
Robert G. Wilson v, Jun 08 2001
STATUS
approved