(49G & 38G & Prime) OEIS A111138: No Short Description

[Gerald H]

And here a programme to insert symbolics in the Sequence App of the 38G to produce the series:

Code:

RECURSE(U,IFTE(U3(N)>1,COMB(U3(N),2),0)+IFTE(U2(N)>2,COMB(U2(N),3),0),0,0)►U1(N):
CHECK 1:
RECURSE(U,ROUND(√(2*N),0),1,2)►U2(N):
RECURSE(U,N-COMB(U2(N),2),0,0)►U3(N):
RECURSE(U,U3(N)-1,0,0)►U4(N):
CHECK 4: