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

Author

Zeljko Vranic, Mar 09 2021

Keywords

• nonn

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).