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Number of mountain numbers (see A134941) with n digits.
4

%I #6 May 05 2023 09:20:51

%S 1,0,8,56,252,784,1792,3108,4166,4352,3544,2232,1068,376,92,14,1

%N Number of mountain numbers (see A134941) with n digits.

%C The total number is 21846.

%e Contribution from _Reinhard Zumkeller_, May 25 2010: (Start)

%e a(1) = A178334(9) = 1;

%e a(2) = A178334(99) - A178334(9) = 1 - 1 = 0;

%e a(3) = A178334(999) - A178334(99) = 9 - 1 = 8;

%e a(4) = A178334(9999) - A178334(999) = 65 - 9 = 56. (End)

%K base,nonn,fini,full

%O 1,3

%A Suggested by _Jonathan Vos Post_, Nov 24 2007 and computed by _Hans Havermann_ and _Joshua Zucker_, Nov 25 2007