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A112040 Terms in A112039 that are divisible by 3, divided by 3. 3
1, 3, 7, 13, 33, 47, 132, 458, 777, 853, 3845, 4395, 4783, 4983, 6038, 6487, 6719, 6957, 11707, 12030, 12688, 13025, 13365, 13709, 14057, 14409, 15861, 17789, 18598, 19008, 19845, 20272, 20702, 21135, 21570, 22010, 22458, 23378, 23850, 24326 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

These integers also form a kind of prime with the a[2*n]/3 as a discriminant. dd = Flatten[Table[If[IntegerQ[a[2*n]/3] == True, Prime[n], {}], {n, 1, 200}]] 2, 3, 5, 7, 13, 17, 31, 67, 89, 97, 227, 239, 251, 257, 281, 293, 307, 311, 419, 421, 433, 439, 443, 449, 457, 461, 487, 521, 541, 547, 563, 569, 571, 577, 587, 593, 599, 607, 613, 617, 641, 643, 647, 653, 673, 743, 751, 769, 853, 857, 859, 863, 877, 881, 911, 919, 929, 947, 953, 967, 977, 983, 991, 997, 1009, 1031, 1039, 1063

LINKS

Table of n, a(n) for n=1..40.

FORMULA

a(0)=1/2 a(n) = a(n-1) + Prime[n]/2 if a[2*n]/3 is an Integer then aout=a[2*n]/3

MATHEMATICA

a[0] = 1/2; a[n_] := a[n] = a[n - 1] + Prime[n]/2 cc = Flatten[Table[If[IntegerQ[a[2*n]/3] == True, a[2*n]/3, {}], {n, 1, 200}]]

CROSSREFS

Sequence in context: A292448 A222227 A152981 * A222187 A084611 A078454

Adjacent sequences:  A112037 A112038 A112039 * A112041 A112042 A112043

KEYWORD

nonn

AUTHOR

Roger L. Bagula, Nov 28 2005

STATUS

approved

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Last modified October 17 19:18 EDT 2019. Contains 328127 sequences. (Running on oeis4.)