A342371 Partial sums of A051697.
2, 4, 6, 9, 12, 17, 22, 29, 36, 43, 54, 65, 76, 89, 102, 115, 132, 149, 166, 185, 204, 223, 246, 269, 292, 315, 338, 367, 396, 425, 454, 485, 516, 547, 578, 615, 652, 689, 726, 763, 804, 845, 886, 929, 972, 1015, 1062, 1109, 1156, 1203, 1250, 1303, 1356, 1409
Offset: 0
Keywords
Examples
n=1, closest prime is 2, add 2; a(1) = 2 + 2 = 4; n=2, closest prime is 2, add 2; a(2) = 4 + 2 = 6; n=3, closest prime is 3, add 3; a(3) = 6 + 3 = 9; n=4, closest prime is 3 (taking the smaller of the equal closest primes 3 and 5, as in A051697), add 3 - a(4) = 9 + 3 = 12.
Crossrefs
Cf. A051697.
Programs
-
Mathematica
Accumulate@ Table[MinimalBy[Prime[If[n < 2, 1, PrimePi[n]] + {0, 1}], Abs[n - #] &][[1]], {n, 0, 53}] (* Michael De Vlieger, Mar 12 2021 *)
Formula
a(n) = a(n-1) + A051697(n).