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A154784
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Row sums of triangle in A154721.
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4
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0, 4, 6, 16, 10, 24, 28, 32, 54, 60, 44, 96, 52, 56, 120, 96, 102, 144, 76, 120, 210, 176, 138, 288, 200, 156, 324, 168, 174, 420, 186, 320, 396, 204, 350, 504, 370, 380, 546, 400, 328, 756, 344, 352, 900, 368, 376, 672, 392, 600
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| a(n) is even for all n.
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LINKS
| Nathaniel Johnston, Table of n, a(n) for n = 1..10000
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FORMULA
| a(n) = A154783(n)-n.
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MAPLE
| isnotcomp:=proc(n)return (n=1 or isprime(n)) end:
for n from 1 to 50 do rsum:=0: for k from 1 to 2*n-1 do if(not k=n and (isnotcomp(k) and isnotcomp(2*n-k)))then rsum:=rsum+k:fi:od: printf("%d, ", rsum):od: # Nathaniel Johnston, Apr 19 2011
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CROSSREFS
| Cf. A154720, A154721, A154723, A154783, A154785, A154786.
Sequence in context: A123667 A129597 A088843 * A062955 A174932 A133092
Adjacent sequences: A154781 A154782 A154783 * A154785 A154786 A154787
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KEYWORD
| easy,nonn
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AUTHOR
| Omar E. Pol (info(AT)polprimos.com), Jan 15 2009
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EXTENSIONS
| Edited by Omar E. Pol (info(AT)polprimos.com), Jan 17 2009
a(11) - a(50) from Nathaniel Johnston (nathaniel(AT)nathanieljohnston.com), Apr 19 2011
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