A262615
Amicable digital pairs: A262091 and A262092 interleaved.
Original entry on oeis.org
136, 244, 919, 1459, 2178, 6514, 58618, 76438, 89883, 157596, 63804, 313625, 2755907, 6586433, 8139850, 9057586, 144839908, 1043820406, 277668893, 756738746, 304162700, 344050075, 4370652168, 11346057072, 21914086555935085, 37878721692554416, 187864919457180831, 375609204308055082, 13397885590701080090, 40091536165423401387
Offset: 1
A262091
Amicable digital pairs: The smaller number of a pair (x,y) with x <> y such that, in decimal notation and with an appropriate number of leading zeros prepended, x=(x_m...x_1x_0){10}, y=(y_m...y_1y_0){10}, x = y_m^m + ... + y_1^m + y_0^m, and y = x_m^m + ... + x_1^m + x_0^m.
Original entry on oeis.org
136, 919, 2178, 58618, 89883, 63804, 2755907, 8139850, 144839908, 277668893, 304162700, 4370652168, 21914086555935085, 187864919457180831, 13397885590701080090, 19095442247273220984552, 108493282045082839040458, 1553298727699254868304830
Offset: 1
a(1) is amicably paired to 244, because 1^3 + 3^3 + 6^3 = 244 and 2^3 + 4^3 + 4^3 = 136.
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# print pairs with leading zeros
from _future_ import print_function
from itertools import combinations_with_replacement
for m in range(2,11):
fs = '0'+str(m+1)+'d'
for c in combinations_with_replacement(range(10),m+1):
n = sum(d**m for d in c)
r = sum(int(q)**m for q in str(n))
rlist = sorted(int(d) for d in str(r))
rlist = [0]*(m+1-len(rlist))+rlist
if n < r and rlist == list(c):
print(format(n,fs),format(r,fs)) # Chai Wah Wu, Jan 04 2016
A264951
Amicable digital numbers.
Original entry on oeis.org
136, 244, 919, 1459, 2178, 6514, 58618, 63804, 76438, 89883, 157596, 313625, 2755907, 6586433, 8139850, 9057586, 144839908, 277668893, 304162700, 344050075, 756738746, 1043820406, 4370652168, 11346057072, 21914086555935085, 37878721692554416, 187864919457180831, 375609204308055082, 13397885590701080090, 40091536165423401387
Offset: 1
- K. Oséki, A problem of number theory, Proceedings of the Japan Academy 36 (1960), 578-587.
A264958
Amicable digital pair: the pairs from A262615 ordered by their smallest member.
Original entry on oeis.org
136, 244, 919, 1459, 2178, 6514, 58618, 76438, 63804, 313625, 89883, 157596, 2755907, 6586433, 8139850, 9057586, 144839908, 1043820406, 277668893, 756738746, 304162700, 344050075, 4370652168, 11346057072, 21914086555935085, 37878721692554416, 187864919457180831, 375609204308055082, 13397885590701080090, 40091536165423401387
Offset: 1
Showing 1-4 of 4 results.
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