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%I #15 Mar 06 2021 01:32:20
%S 90,270,375,418,450,630,726,735,778,810,990,999,1146,1170,1350,1371,
%T 1386,1395,1446,1494,1530,1710,1731,1890,1998,2070,2218,2250,2394,
%U 2430,2482,2610,2790,2842,2898,2970,3150,3171,3186,3195,3312,3330,3366,3375,3393
%N Numbers k such that cos(k) = sin(d(1)*d(2)*...*d(q)) where d(1)d(2)...d(q) denotes the decimal expansion of k and the angles are in degrees.
%e 2482 is in the sequence because cos(2482°) = sin(2*4*8*2°)= 0.7880107536067219... (A019861).
%p with(numtheory):err:=1/10^10:Digits:=20:for n from 1 to 5000 do:x:=convert(n,base,10):n1:=nops(x):p:=product('x[i]', 'i'=1..n1):s1:=evalf(cos(n*Pi/180)):s2:=evalf(sin(p*Pi/180)):if abs(s1-s2)<err then printf(`%d, `,n):else fi:od:
%Y Cf. A237129.
%K nonn,base
%O 1,1
%A _Michel Lagneau_, Feb 04 2014
%E Name edited by _Jon E. Schoenfield_, Sep 12 2017
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