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Number of permutations of {0, 1, ..., n} that start with 0 and have pairwise distinct differences between adjacent terms.
1

%I #12 Aug 02 2021 01:19:21

%S 1,1,1,3,7,27,94,425,2100,12252,79865,576220,4532457,38657929,

%T 354600915,3485914368,36545825768,407149542540

%N Number of permutations of {0, 1, ..., n} that start with 0 and have pairwise distinct differences between adjacent terms.

%C a(n) <= A131529(n).

%o (PARI) { A346658(n) = my(q,r=0); forperm(n,p, q=vector(n,i,p[i]-if(i>1,p[i-1])); r+=(#vecsort(q,,8)==n); ); r; }

%Y Cf. A131529.

%K more,nonn

%O 0,4

%A _Max Alekseyev_, Jul 27 2021

%E a(14)-a(17) from _Martin Ehrenstein_, Aug 01 2021