A276170 Let n have j digits {d_j, d_(j-1), ..., d_2, d_1}. Sequence lists numbers n such that n = d_j^b_j + d_(j-1)^b_(j-1) + ... + d_2^b_2 + d_1^b_1 for some permutation {b_j, b_(j-1), ..., b_2, b_1} of the digits.

1, 1364, 3435, 4155, 4316, 4355, 17463, 48625, 63725, 78215, 117693, 136775, 137456, 137529, 164726, 184746, 196753, 264719, 326617, 326671, 397612, 423858, 516974, 637395, 652812, 653285, 653957, 687523, 834272, 936627, 1374962, 1617349, 1679812, 1683397, 1683514

Offset

1,2

Comments

0^0 is not admitted.

652812 is the first number with two essentially different permutations:

6^1 + 5^8 + 2^5 + 8^6 + 1^2 + 2^2 = 6^2 + 5^8 + 2^1 + 8^6 + 1^5 + 2^2 = 652812.

Links

Table of n, a(n) for n=1..35.

Paolo P. Lava, First 100 terms with applicable permutations

Example

One of the permutations of {1,3,6,4} is {6,1,4,3} and 1^6+3^1+6^4+4^3 = 1364.

Maple

with(combinat); P:= proc(q) local a, b, c, d, j, k, ok, n;
for n from 1 to q do ok:=1; d:=ilog10(n)+1; a:=convert(n, base, 10); b:=permute(a, d);
for k from 1 to nops(b) do c:=0; for j from 1 to d do
if a[j]=0 and b[k][j]=0 then ok:=0; break; else c:=c+a[j]^b[k][j];  fi; od;
if ok=1 then if c=n then print(n); break; fi; fi; od; od; end: P(10^6);

Crossrefs

Cf. A046253, A166623.

Sequence in context: A119521 A004930 A004950 * A028486 A281479 A013592

Adjacent sequences: A276167 A276168 A276169 * A276171 A276172 A276173

Keyword

nonn,base,fini,easy

Author

Paolo P. Lava, Aug 23 2016

Status

approved