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A176266 Binomial(prime(n),s)/prime(n) where s is the sum of the decimal digits of n.

%I A176266 #13 Oct 25 2020 11:37:11
%S A176266 1,1,2,5,42,132,1144,3978,35530,1,15,210,2470,22386,228459,2908360,
%T A176266 37584261,284291205,3701413144,35,852,19019,349812,6529292,132435472,
%U A176266 2000945100,24366118700,328386663605,3520256293710,2072,81375,2271776,59988852,1227434238,33401522154,584134601050,11919696387170,234924043375476,3924875235562164,208335
%N A176266 Binomial(prime(n),s)/prime(n) where s is the sum of the decimal digits of n.
%C A176266 For n = 10^p, a(n) = 1.
%F A176266 a(n) = A007318( A000040(n), A007953(n))/A000040(n).
%F A176266 a(n) = A060604(n)/A000040(n), n<10.
%e A176266 a(5) = 42 because prime(5) = 11, s = 5,  binomial(11,5)/11 = 462/11=42.
%e A176266 a(16)=2908360 because prime(16)=53, s=7, binomial(53,7)/53 =154143080/53 = 2908360.
%p A176266 A176266 := proc(n) binomial(ithprime(n),A007953(n))/ithprime(n) ; end proc:
%p A176266 seq(A176266(n),n=1..20) ;
%t A176266 Table[Binomial[Prime[n],Total[IntegerDigits[n]]]/Prime[n],{n,40}] (* _Harvey P. Dale_, Oct 25 2020 *)
%o A176266 (Sage) A176266 = lambda n: binomial(nth_prime(n), sum(n.digits()))/nth_prime(n) # _D. S. McNeil_, Dec 08 2010
%Y A176266 Cf. A075872.
%K A176266 nonn,base
%O A176266 1,3
%A A176266 _Michel Lagneau_, Dec 07 2010