A123139 a(n) = prime(n)*(prime(n + 1) + 1) - (n^3 + sum of digits of n^3).

6, 2, 4, 10, 21, 9, -13, -64, -57, -73, -161, -192, -412, -697, -855, -935, -1272, -1702, -2063, -2754, -3439, -4031, -4714, -5120, -5750, -7098, -8586, -10201, -11989, -12545, -13055, -14716, -16784, -18473, -20253, -22825, -24924, -27514, -30288, -32870, -36369, -39363, -42481, -46996, -51743

Offset: 1

Author

Herman Jamke (hermanjamke(AT)fastmail.fm), Sep 30 2006

Keywords

• sign
• base

Links

• A. Frank & P. Jacqueroux, International Contest, 2001. Item 30 = Item 21 - Item 24.

Programs

Mathematica

Table[Prime[n](Prime[n+1]+1)-(n^3+Total[IntegerDigits[n^3]]),{n,50}] (* Harvey P. Dale, Jul 03 2021 *)

PARI

for(n=1,50,sda=eval(Vec(Str(n^3)));print1(prime(n)*(prime(n+1)+1)-(n^3+sum(i=1,length(sda),sda[i])),","))

Formula

a(n) = A123134(n) - A123135(n). - Michel Marcus, Dec 03 2013