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A237131 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 units of degrees. 0
90, 270, 375, 418, 450, 630, 726, 735, 778, 810, 990, 999, 1146, 1170, 1350, 1371, 1386, 1395, 1446, 1494, 1530, 1710, 1731, 1890, 1998, 2070, 2218, 2250, 2394, 2430, 2482, 2610, 2790, 2842, 2898, 2970, 3150, 3171, 3186, 3195, 3312, 3330, 3366, 3375, 3393 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..45.

EXAMPLE

2482 is in the sequence because cos(2482°) = sin(2*4*8*2°)= 0.7880107536067219... (A019861).

MAPLE

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:

CROSSREFS

Cf. A237129.

Sequence in context: A235081 A074213 A231961 * A255784 A250877 A250878

Adjacent sequences:  A237128 A237129 A237130 * A237132 A237133 A237134

KEYWORD

nonn,base

AUTHOR

Michel Lagneau, Feb 04 2014

EXTENSIONS

Name edited by Jon E. Schoenfield, Sep 12 2017

STATUS

approved

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Last modified October 22 06:02 EDT 2018. Contains 316432 sequences. (Running on oeis4.)