A184593 -id:A184593 - cp's OEIS frontend

A184594 Where A184593, the difference between 5n and A101306(n), becomes a new record in either direction.

1, 2, 5, 6, 20, 21, 35, 62, 64, 65, 67, 97, 159, 198, 267, 444, 449, 499, 761, 764, 800, 801, 802, 803, 804, 810, 886, 1413, 1435, 1613, 1614, 1615, 1634, 2566, 2568, 4162, 4653, 6115, 6118, 6120, 6121, 6124, 6136, 7063, 7070, 7071, 7075, 7076, 7118, 7119, 7424

Offset: 1

Robert G. Wilson v, Jan 17 2011

Use the first Mathematica program in A184593 to produce the difference.

Cf. A184593.

k = 1; p = 2; lst = {}; mn = mx = s = 0; While[p < 10^5, s = s + Mod[p, 10]; d = s - 5 k; If[ Positive@ d, If[d > mx, AppendTo[lst, k]; mx = d], If[d < mn, AppendTo[lst, k]; mn = d]]; k++; p = NextPrime@ p]; lst

A277097 a(n) = 5 - (prime(n) mod 10).

Original entry on oeis.org

3, 2, 0, -2, 4, 2, -2, -4, 2, -4, 4, -2, 4, 2, -2, 2, -4, 4, -2, 4, 2, -4, 2, -4, -2, 4, 2, -2, -4, 2, -2, 4, -2, -4, -4, 4, -2, 2, -2, 2, -4, 4, 4, 2, -2, -4, 4, 2, -2, -4, 2, -4, 4, 4, -2, 2, -4, 4, -2, 4, 2, 2, -2, 4, 2, -2, 4, -2, -2, -4, 2

Offset: 1

Dimitris Valianatos, Sep 29 2016

Except for a(1)=3 and a(3)=5 the entries are either {-4, -2, 2, 4} and occur in roughly equal ratios. - Robert G. Wilson v, Nov 04 2016

			For n = 10 and prime(10) = 29, so a(10) = 5 - 9 = -4.

Cf. A007652, A184593.

f[n_] := 5 - Mod[Prime[n], 10]; Array[f, 71] (* Robert G. Wilson v, Nov 04 2016 *)

a(n) = my(p=prime(n)); (10*(p\10)+5) - p; \\ Michel Marcus, Sep 30 2016

a(n) = 5 - A007652(n). - Robert G. Wilson v, Nov 04 2016

cp's OEIS Frontend

A184594 Where A184593, the difference between 5n and A101306(n), becomes a new record in either direction.

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