This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A372563 #11 May 21 2024 13:44:05 %S A372563 0,2,1,3,12,1,12,11,18,3,3,85,29,64,1,17,23,187,47,36,3,9,97,19,931, %T A372563 53,106,1,50,17,291,75,733,71,54,3,36,504,35,889,31,2533,77,148,5,21, %U A372563 121,1620,65,1011,111,1639,187,288,1,3,171,505,11840,59,2197,119,4927,179,90,5 %N A372563 Square array A(n, k) = A246278(1+n, k) - sigma(A246278(n, k)), read by falling antidiagonals, where A246278 is the prime shift array. %H A372563 Antti Karttunen, <a href="/A372563/b372563.txt">Table of n, a(n) for n = 1..11325; the first 150 antidiagonals, flattened</a> %H A372563 <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a> %H A372563 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a> %F A372563 A(n, k) = A286385(A246278(n, k)) = A246278(1+n, k) - A355927(n, k). %e A372563 The top left corner of the array: %e A372563 k= 1 2 3 4 5 6 7 8 9 10 11 12 %e A372563 2k= 2 4 6 8 10 12 14 16 18 20 22 24 %e A372563 ---+------------------------------------------------------------------------- %e A372563 1 | 0, 2, 3, 12, 3, 17, 9, 50, 36, 21, 3, 75, %e A372563 2 | 1, 12, 11, 85, 23, 97, 17, 504, 121, 171, 29, 635, %e A372563 3 | 1, 18, 29, 187, 19, 291, 35, 1620, 505, 265, 25, 2525, %e A372563 4 | 3, 64, 47, 931, 75, 889, 65, 11840, 795, 1259, 93, 12503, %e A372563 5 | 1, 36, 53, 733, 31, 1011, 59, 12456, 1561, 817, 89, 16853, %e A372563 6 | 3, 106, 71, 2533, 111, 2197, 157, 52580, 1839, 2987, 107, 50507, %e A372563 7 | 1, 54, 77, 1639, 119, 2163, 49, 41580, 3193, 3101, 127, 53357, %e A372563 8 | 3, 148, 187, 4927, 113, 6197, 211, 142280, 8283, 4969, 183, 179083, %e A372563 9 | 5, 288, 179, 11669, 305, 9481, 277, 414720, 6965, 13421, 239, 374459, %e A372563 10 | 1, 90, 187, 4531, 131, 7685, 73, 190980, 12649, 6303, 137, 293947, %e A372563 11 | 5, 376, 301, 19869, 247, 18395, 331, 919856, 17173, 17161, 425, 906981, %e A372563 12 | 3, 274, 167, 16861, 255, 13189, 349, 899540, 10335, 17099, 367, 777083, %o A372563 (PARI) %o A372563 up_to = 66; %o A372563 A246278sq(row,col) = if(1==row,2*col, my(f = factor(2*col)); for(i=1, #f~, f[i,1] = prime(primepi(f[i,1])+(row-1))); factorback(f)); %o A372563 A003961(n) = { my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); }; %o A372563 A286385(n) = (A003961(n)-sigma(n)); %o A372563 A372563sq(row,col) = A286385(A246278sq(row,col)); %o A372563 A372563list(up_to) = { my(v = vector(up_to), i=0); for(a=1,oo, for(col=1,a, i++; if(i > up_to, return(v)); v[i] = A372563sq(col,(a-(col-1))))); (v); }; %o A372563 v372563 = A372563list(up_to); %o A372563 A372563(n) = v372563[n]; %Y A372563 Cf. A000203, A003961, A246278, A286385, A355927. %Y A372563 Cf. A046933 (column 1). %Y A372563 Cf. also A355924, A372562. %K A372563 nonn,tabl %O A372563 1,2 %A A372563 _Antti Karttunen_, May 21 2024