A009190 - cp's OEIS frontend

A009190 "2p-twin peaks": a(n) is the least x with lpf(x) = lpf(x + 2p) = p = prime(n) and lpf(y) < p for all x < y < x + 2p, where lpf = least prime factor; a(n) = -1 if no such x exists.

n	a(n)
20	7310131732015251470110369
21	2061519317176132799110061
22	3756800873017263196139951
23	6316254452384500173544921
24	14733008374252975993271023
25	532045863029111910656094569
26	476592878661578285779747459

[7310131732015251470110369, 2061519317176132799110061, 3756800873017263196139951, 6316254452384500173544921, 14733008374252975993271023, 532045863029111910656094569, 476592878661578285779747459]

cp's OEIS Frontend

A009190 "2p-twin peaks": a(n) is the least x with lpf(x) = lpf(x + 2p) = p = prime(n) and lpf(y) < p for all x < y < x + 2p, where lpf = least prime factor; a(n) = -1 if no such x exists.

Table of values

List of values