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A087884
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a(n) = PrimePi[PrimePi[n-1]] + Prime[Abs[n - Prime[n-1]]]
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0
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3, 4, 13, 15, 25, 31, 43, 63, 70, 92, 106, 110, 130, 154, 183, 185, 215, 233, 237, 267, 281, 315, 357, 377, 383, 401, 405, 425, 504, 526, 568, 574, 622, 624, 658, 688, 714, 748, 779, 793, 859, 863, 883, 887, 973, 1039, 1057, 1067, 1093, 1115, 1123, 1199
(list; graph; refs; listen; history; internal format)
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OFFSET
| 4,1
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COMMENTS
| A prime based reinversion sequence based on the A004001 pattern.
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MATHEMATICA
| prid[n_Integer?Positive] := prid[n] =PrimePi[PrimePi[n-1]] + Prime[Abs[n - Prime[n-1]]] prid[1] = prid[2] = 1 digits=256 a=Table[prid[n], {n, 4, digits+4}]
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CROSSREFS
| Cf. A004001.
Sequence in context: A109474 A053910 A105074 * A057570 A024853 A023857
Adjacent sequences: A087881 A087882 A087883 * A087885 A087886 A087887
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KEYWORD
| nonn
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AUTHOR
| Roger L Bagula (rlbagulatftn(AT)yahoo.com), Oct 12 2003
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