A308126 Positive integers equal to the permanent of Hankel matrix formed by their decimal digits.

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 562, 962, 26240, 85440

Offset: 1

Author

Paolo P. Lava, May 14 2019

Keywords

• nonn
• base
• more

Examples

			     | 5 6 2 |
perm | 6 2 6 | = 5*2*5 + 6*6*2 + 2*6*6 + 2*2*2 + 6*6*5 + 5*6*6 = 562.
     | 2 6 5 |
		

Links

• Eric Weisstein's World of Mathematics, Permanent
• Wikipedia, Hankel matrix

Crossrefs

Cf. A306714, A306853.

Programs

Maple

with(linalg): P:=proc(q) local c, d, k, n, t: print(0);
for n from 1 to q do c:=convert(n, base, 10): t:=[]:
for k from 1 to nops(c) do t:=[op(t), 0]: od: d:=t: t:=[]:
for k from 1 to nops(c) do t:=[op(t), d]: t[k, -k]:=1: od:
if permanent(evalm(toeplitz(c) &* t))=n then print(n); fi:
od: end: P(10^8);