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%I #14 Mar 28 2017 15:05:48
%S 5,21,24,16,6,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
%T 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
%U 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
%N a(n) is the number of n-subsets [n=1,2,...,10] of the 10 decimal digits from which no prime numbers can be constructed. See also A099653.
%C Number of "antiprime-digit-subclasses".
%C Subsets were selected from {0, 2, 4, 5, 6, 8} and {0, 3, 6, 9} digit collections.
%F a(n) = binomial(6,n) + binomial(4,n) for n > 1.
%e n=1: {0,2,4,6,8} represent the relevant 1-subsets so a[1]=5.
%e Total number of prime irrelevant subset-classes from the 1023 nonempty k-digit-subsets equals 5 + 21 + 24 + 16 + 6 + 1 = 73 = 1023 - 950. See also A099653.
%e The "antiprime n-digit-collections" are taken from {0,2,4,5,6,8} or {0,3,6,9}, of which only composites can be constructed.
%t Table[Binomial[6, n] + Binomial[4, n] - 5 Boole[n == 1], {n, 100}] (* _Michael De Vlieger_, Mar 26 2017 *)
%o (PARI) a(n) = binomial(6, n) + binomial(4, n) - 5*(n==1); \\ _Indranil Ghosh_, Mar 27 2017
%o (Python)
%o from sympy import binomial
%o def a(n): return binomial(6, n) + binomial(4, n) - 5*(n==1) # _Indranil Ghosh_, Mar 27 2017
%Y Cf. A099651, A099654, A099756.
%K base,nonn
%O 1,1
%A _Labos Elemer_, Nov 15 2004
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