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A130598 A shell geometric model of the nucleus. The location of the magic numbers. A triangle. 13
10, 1111, 10, 111111, 11, 1110, 11111110, 1111, 11, 111111, 1111111110, 111111, 11, 1111, 11111111, 111111111110, 11111111, 1111, 11, 111111, 1111111111, 11111111111110, 1111111111, 111111, 11, 1111, 11111111, 111111111111 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The magic numbers of the atomic nucleus: 2, 8, 20, 28, 50, 82, 126. 0 is the location of a magic number. 10 or 11 is equal to 2 protons (or neutrons). 1110 or 1111 is equal to 2+2 protons (or neutrons). 111111 is equal to 2+2+2 protons (or neutrons)... The 2D model is a triangle and a spiral. The 3D model is a double tetrahedron and a double spiral.

LINKS

Table of n, a(n) for n=1..28.

EXAMPLE

......|----------------------- h -------------------|.....

......|.....|----------------- g --------------|....|.....

......|.....|.....|----------- f ---------|....|....|.....

......|.....|.....|....|------ d -----|...|....|....|.....

......|.....|.....|....|...|-- p -|...|...|....|....|.....

......|.....|.....|....|...|.. s .|...|...|....|....|.....

......|.....|.....|....|...|......|...|...|....|....|.....

......|.....|.....|....|......10......|...|....|....|.....

......|.....|.....|......1111....10.......|....|....|.....

......|.....|.......111111....11....1110.......|....|.....

......|........11111110..1111....11....111111.......|.....

.......1111111110...111111....11....1111...11111111.|.....

111111111110...11111111..1111....11....111111...1111111111

......|.....|.....|....|...|..|...|...|...|....|....|.....

......|.....|.....|....|...|..|1/2|...|...|....|....|.....

......|.....|.....|....|...|-- 3/2 ---|...|....|....|.....

......|.....|.....|....|------ 5/2 -------|....|....|.....

......|.....|.....|----------- 7/2 ------------|....|.....

......|.....|----------------- 9/2 -----------------|.....

......|---------------------- 11/2 -----------------------

CROSSREFS

Cf. A056951, A130517, A130556, A130602.

Sequence in context: A267246 A266589 A015026 * A267595 A266621 A223119

Adjacent sequences:  A130595 A130596 A130597 * A130599 A130600 A130601

KEYWORD

nonn,tabl

AUTHOR

Omar E. Pol, Aug 10 2007

STATUS

approved

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Last modified November 21 12:11 EST 2019. Contains 329370 sequences. (Running on oeis4.)