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Positive integers equal to the permanent of Hankel matrix formed by their decimal digits.
1

%I #6 May 14 2019 11:26:00

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

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

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Permanent.html">Permanent</a>

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Hankel_matrix">Hankel matrix</a>

%e | 5 6 2 |

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

%e | 2 6 5 |

%p with(linalg): P:=proc(q) local c, d, k, n, t: print(0);

%p for n from 1 to q do c:=convert(n, base, 10): t:=[]:

%p for k from 1 to nops(c) do t:=[op(t), 0]: od: d:=t: t:=[]:

%p for k from 1 to nops(c) do t:=[op(t), d]: t[k, -k]:=1: od:

%p if permanent(evalm(toeplitz(c) &* t))=n then print(n); fi:

%p od: end: P(10^8);

%Y Cf. A306714, A306853.

%K nonn,base,more

%O 1,3

%A _Paolo P. Lava_, May 14 2019