A265843 Number of moves for the prime winding graph to have a zero x coordinate value.

1, 2, 6, 12, 18, 24, 36, 42, 48, 1150, 1154, 1180, 1188, 1206, 1240, 1268, 1688, 1970, 1982, 2016, 2028, 2040, 2194, 3270, 3300, 3308, 3346, 3360, 3372, 3390, 3408, 3438, 3480, 3510, 3518, 3554, 3562, 4042, 4542, 4554, 4574, 5136, 5164, 5174

Offset

1,2

Comments

Define the prime winding graph as follows: Starting at (0,0) draw a straight line up the y-axis until the first prime is attained. Once the first prime is attained draw a straight line 90 degrees to the left until the second prime is attained. When the second prime is attained draw a straight line 90 degrees to the left until the third prime is attained. Repeat this process for all primes up to a specified number. The above sequence represents the number of moves required for the x coordinate to be equal to zero, where one move is equal to a line of length 1.

Links

Table of n, a(n) for n=1..44.

Gregory Whittaker, Prime winding graph

Gregory Whittaker, JavaScript code for prime winding graphK

Prog

(PARI) lista(nn) = {x = 0; y = 0; dir = 1; for (n=1, nn, x += round(cos(dir*Pi/2)); y += round(sin(dir*Pi/2)); if (!x, print1(n, ", ")); if (isprime(n), dir ++); dir = dir % 4; ); } \\ Michel Marcus, Dec 17 2015

Crossrefs

Sequence in context: A304450 A085345 A348774 * A276829 A032371 A162802

Adjacent sequences: A265840 A265841 A265842 * A265844 A265845 A265846

Keyword

nonn

Author

Gregory Whittaker, Dec 16 2015

Status

approved