the Buddha did not exist as a truth or ultimate reality to begin with and all that could be said to have existed has been utterly extinguished, having no residue for a future with the arahant's death all modes of existence come to an end.
"Now what, bhikkhus, is the Nibbana-element with no residue left? Here a bhikkhu is an arahant, one whose taints are destroyed, the holy life fulfilled, who has done what had to be done, laid down the burden, attained the goal, destroyed the fetters of being, completely released through final knowledge. For him, here in this very life, all this is experience, not being delighted in, will be extinguished. That, bhikkhus, is called the Nibbana-element with no residue left.
"These bhikkhus, are the two Nibbana-elements."
These two Nibbana-elements were made known
By the Seeing One, stable, and unattached:
One is the element seen here and now
With residue, but with the cord of being destroyed;
The other, having no residue for the future,
Is that wherein all modes of being utterly cease.
Having understood the unconditioned state,
Released in mind with the cord of being destroyed,
They have attained to the Dhamma-essence.
Delighting in the destruction (of craving),
Those stable ones have abandoned all being.
"And so, my friend Yamaka — when you can't pin down the Tathagata as a truth or reality even in the present life — is it proper for you to declare, 'As I understand the Teaching explained by the Blessed One, a monk with no more effluents, on the break-up of the body, is annihilated, perishes, & does not exist after death'?"
"And so, Anuradha — when you can't pin down the Tathagata as a truth or reality even in the present life — is it proper for you to declare, 'Friends, the Tathagata — the supreme man, the superlative man, attainer of the superlative attainment — being described, is described otherwise than with these four positions: The Tathagata exists after death, does not exist after death, both does & does not exist after death, neither exists nor does not exist after death'?"
"Monks, I will teach you the All. Listen & pay close attention. I will speak."
"As you say, lord," the monks responded.
The Blessed One said, "What is the All? Simply the eye & forms, ear & sounds, nose & aromas, tongue & flavors, body & tactile sensations, intellect & ideas. This, monks, is called the All.  Anyone who would say, 'Repudiating this All, I will describe another,' if questioned on what exactly might be the grounds for his statement, would be unable to explain, and furthermore, would be put to grief. Why? Because it lies beyond range."
It is not proper to declare that the Tathagata remembers you but when you recollect the Buddha, the Dhamma and the Sangha, that is a help to you.